Car Coasting in Neutral

Leave it in gear. You won't save any more petrol in neutral and your brakes will wear out more quickly.

I agree with Lyn. I'm assuming the car is an automatic, otherwise you would just use the clutch as neutral. If you overshoot neutral, you will be in reverse. Not cool.

I take my foot off the gas and try to coast up to the light, only applying a little brake pressure to stop. If I know it's a long light, I'll put it in park while I'm waiting.

Of course, all of my efforts don't matter. My wife accelerates toward red lights, and slams on the brakes when she has to stop. I just get to replace brake pads twice a year.

In this country, it is not considered good practice because if an emergency were to pop up, you would not have power to avoid an accident. Many times, the way to avoid an accident is to accelerate and steer around danger. No power; no control.

Consider why no auto maker has installed a one-way clutch. i.e a clutch that works like a ratchet. When the wheels wanted to go faster than the engine, they could as if the car was in neutral, but normally the engine would drive the wheels.

Years ago, my uncle told me of a car that was designed with such a clutch. I don't recall the maker, the model or the year, but I believe it would have been pre-WWII. He said it got great gas mileage, but downshifting was a bit of a problem. In the end, he said, these clutches were outlawed, mostly for the fact that there is minimal control when slowing down.

Many automatic cars for all intents and purposes have a one-way clutch. My dad's Buick LeSabre (late nineties vintage seventh generation LeSabre) would easily get over 30 miles per gallon on the highway in large part due to the way the thing would coast. Even on modest declines, with his foot off the gas the car would surge well over 70 mph.

Compare that to my little '05 Jetta with the 5-speed. I only get 34 miles per gallon if I baby the thing at 65 mph or less. If I'm hot footing it at 70-75 my mileage drops to about 31 to 32 mpg.

TDI engine option males all the difference in the world. You could almost double your mileage if your car was a TDI.

The TDI engines run foreveer too. I've seen a couple examples still running strong over 350,000 miles without yet seeing their first overhall/rebuild.

Opt for the TDi next time.

(If you do have a TDI then something is seriously wrong)

My wife and I test drove a TDI in 2005 and loved it except one thing. It was $6,000 more than the same gasoline powered Jetta with the 2.slow engine. Back in 2005, here in the mid-Atlantic states, diesel was only about $0.15 a gallon more than gasoline and I ran the numbers. I would have had to drive the car 150,000 miles just to break even based upon the published EPA mileages. As of today, I have 130,000 miles on the car, so I am still money ahead. Given the price of diesel has risen to about 40 cents a gallon more than petrol, the break even point has been driven even further out.

Let's say you have an overall average of 50 miles per gallon with the TDI. That works out to a fuel cost of $0.08 per mile with diesel at $4.00 per gallon.

I have all my fuel records and I have averaged 29.4 mpg over the entire life of my car. With gasoline here at about $3.50 per gallon, my current fuel costs are $0.12 per mile. That is a difference of $0.04 per mile. To make up for price differential between the gasoline Jetta ($15.5k out the door taxes, title, tags) versus the 2005 TDI (Over $21k at that time when we bought) my break even point is still 150,000 even with a generous allowance for TDI mileage. Yes, I know that TDI's can get very good highway mileage but I run about 50/50 highway versus surface streets. I'd be curious to know what sort of mileage TDI's get with a healthy mix of around town and highway driving. (I get about 27 to 28 around town and 31 to 34 highway).

As for durability, VW uses the same blocks and bottom ends for both their gasoline and diesel cars. It's one reason why the gasoline engined cars can be hopped up reliably to over 250 hp. My son is still driving my '87 gasoline Jetta with over 260,000 miles. The engine runs great with no maintenance outside of oil changes, plugs, cap and rotor (and one timing belt at 180k). We still don't add oil between 5,000 mile oil changes.

What sort of maintenance costs do you incur with the TDI's? I don't recall if they have any sort of urea tank, exhaust filters, regen thingy's or whatever.

The only thing my '05 gasoline Jetta has had done to it is tires and oil changes. I'm due for a timing belt and spark plugs. If you lose the timing belt on the newer Jetta's you'll be buying pistons and valves at a minimum. On the old 1.8 GX motors, you can't hit the pistons with the valves no matter what. Wasn't true for the GTi/GLi motors though.

Next time I need a car, I will run the numbers again. We'll see.

Here we have a greater difference between petrol and diesel fuel prices, but we also have a higher road tax on diesel engines.

But if you drive around 20,000 miles a year you start to make money.

But what I really like about diesels is the fact that the fuel is difficult to get burning in the event of an accident with a leaking fuel tank, sparks are simply not enough to get things going until the fuel gets over about 55°C or so, which is pretty impossible....where Petrol explodes at normal daily outside temperatures with a few sparks.....

I also like the fact that the diesels are in comparison to petrol engines, much more substantially built internally, are simpler (though they are getting more and more complicated nowadays, but have still not reached that of modern petrol engines), have no high voltage components and generally last far longer before major repairs are needed.

But each to his own!!!

Your decision makes complete sense. I am always running cost/benefit analysis and I would have likely made the very same decision had I been in your shoes.

I think the biggest difference in our decisions is that you are buy new cars and I buy cars that are at least 3 years old.

Of course I don't dislike newer cars, its just that the depreciation in dollars versus depreciation in remaining utility makes nicely treated used cars a far better value proposition IMHO, even using very conservative estimates for remaining life and additional maintenance costs.

The premium for TDI depreciated rapidly. My guess is that it falls farther on a percentage basis in most cases over the first 3 to 5 years.

I will say finding a used TDI stick shift for sale, even over a relatively large geographic area, requires a little patience, even when you include models, not just a Jetta. So there are some non-monetary costs involved to say the least. My guess would be that there aren't many people who are both: part of the group that buys a new car and replaces it reliably every 3 to 5 years; and part of the group to which the TDI attributes outweigh the costs.

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Don't misunderstand me, I am not denigrating new car buyers! Some people don't like the idea of riding a divorcee around; they are happier inside something that hadn't already been around the block a time or two, as it were.

Moreover, it isn't just a matter of it being their personal choice, it is vital for enough people to make that choice, otherwise the benefit available for buying used would quickly vanish.

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As for maintenance, pretty much only normal expected wear and tear maintenance, with the following exceptions:

-The TDI's (not sure about other engines) use a plastic impeller on the water pump which is known to break free of the shaft, usually starting before 200,000 miles. I will be replacing that in the near future as a preventative measure. I will replace the timing belt at that time.

-The front air dam is poorly designed and likes to snag when backing away from things like inclined driveways or almost-low-enough parking space bumpers (I know there must be a shorter customary term....). I ended up fabricating a belly pan that fits up to, and fills the gap that previously would cause the snags.

-My biggest complaint however is the number of stupid little, mostly unnecessary plastic bullshit accoutrements, mainly in the interior that detaches or breaks. None of it has been critical for safe operation, yet the frequency is both impressive and annoying. Some new piece of plastic crap breaks free or simply breaks about once a month...maybe that is an exaggeration, but it feels continual.

What compounds the aforementioned is that in most case, the replacement of the 50 cent piece of plastic is only available as part of a 50$ or 100$ assembly. My aversion to paying 50$ for something that costs less than 50 cents to make (OK, so comment #31 might be at least 1/3 correct. Blind hogs, acorns, all that.) means I adjust my mirror with my hand.

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You have to have something to complain about right? My complaints in total are easily outweighed, and I would make the same choice again.

Every time I fill up (usually just under 12 gallons) and then look down to check and reset the trip odometer (usually reading in the mid 600s to low 700s) it doesn't bother me that any drink in the car must have a twist cap.

It is VW recommended and also common practice for many years with all TDI engines, to also replace the water pump when replacing the toothed belt. In fact, the official kit has both items in it as do many similar kits supplied by the car industry.....

It has nothing to do with the life of the impeller really (what you say may even be true!), but its the poor original engine design whereby the pump is driven by the same toothed belt as the valves and if the pump bearings fail, it usually causes major engine damage as well.....some 10 years ago, a friend paid €6,000 to get the engine repaired...over $7,500.......more than some cars will even be worth.....

I don't know at what mileage VW USA recommends timing belt replacement, but here its usually around either 100,000 or 120,000 Kilometers ONLY! Certainly nothing like 200,000 miles which is around 320,000 kilometers or so.....!!! I would expect the USA to be similar to Germany in that respect myself.......Its easily checked out in the service manual for a USA TDI car.

These are the sort of good tips that a TDI customer, not going to a proper VW specialist, or VW themselves misses out on and causes a possible major problem with his engine......

There is also the problem in the USA (I am told) of people not using the correct oils in TDI engines as they have all been set for Full Synthetic oil, at least here in Germany, since 1998 or so......they have a sort of computer that calculates when an oil and filter change should be made, depending upon the usage. My computer suggested between 33,000 and 35,000 Kms between changes......20,000 miles or so at a guess....

My old favorite German saying comes to mind again:-

"He saves money, no matter what it costs!"

Andy and Truth,

Thanks for the inputs on the maintenance issues specific to the TDI's. The only problem with used is the good cars don't get traded in or they are so close in price to new, you would say what's the point? Add to that, my missus is a bit, let's say 'particular' about things (OCD) so new cars make life easier. That being said, we drive our cars into the ground. Our first new car is now being driven by our son. It's 5 years older than he is.

I think VW recommends 90,000 miles on the 2.slow engine. My Mark II Jetta went 180,000 miles before it threw a few 'teeth' off of the belt. Age and environmental exposure plays a part too in the degradation of the rubbers so older cars with lower mileage my need them sooner.

Cheers !!

lyn and kramat are right.

However, I coast as much as I can on my stick shift. Especially on slopes. If you have a stick shift like me, consider not just the brake's wear and tear but also the clutch's: which of your options require a higher number gear switching?

My position is that if you cant afford the fuel or need to worry about how you use every drop you buy you probably cant afford the vehicle.

Now if you are already driving the smallest cheapest most fuel efficient toy car you can find and still having trouble with the fuel and general maintenance bills you probably either need to find a better job or get a bicycle or as a last resort walk!

Better yet, coast in reverse and get some of your gas back!

Wow...you beat me to it!

I did the unusual step of reading thru this entire set of interesting posts-I vote for Brave Sir Robin -- Long distance coasting with the input shaft not turning on most automatics and some manuals (Triumph TR7, for instance) means the critical transmission bearings are not getting adequate lubrication. I like super miling, where you go to maximum possible speed and switch off the engine. Triples mileage. Keep in mind that coasting, of any sort, while not under power is illegal in many jurisdictions. (Fomer FIA & SCCA Nat'l license holder)

True about some manual transmissions needing input shaft rotation for lube. One way to verify that is to go to an RV website and lookup dinghy vehicles. If they say you can tow the car on "all fours", then it can coast with the engine off with little chance of damage, although I cannot in good conscience recommend engine off coasting.

The way I look at the situation is thus: If a person is that interested in improving mileage, chances are they are a very attentive (maybe anal? ) driver and will be far less likely to be involved in an accident than the driver yakking on the phone up to their ear, or looking down between their legs so they don't get caught to text their bubble-headed teen-aged friend, or shaving their beard on the way to work, or applying eye-liner and mascara on the way to the office, or arranging a playlist on their iAnything, or placating their screaming progeny in the back seat, or . . . .

Take a look as you drive around. Most skids are two nice straight lines, not four curving lines.
Skidding tires cannot be steered. I have avoided a couple of collisions at the last second or two by taking my foot off the brake so that the car can turn. I have no argument with the rest of your post.

If you drove with a car fitted with ABS, you would in most situations have the benefit of (without having to think about it or do anything extra) of both full brakes AND steering.....you should try it someday in any empty parking lot with an ABS fitted car, especially when its wet.

I also learnt "Cadence" Braking when younger......

Most (good) modern cars have ABS as standard. Here anyway. I cannot speak for where you live.

ABS has some minor limitations when on loose earth, grit or snow, but in most other situations, its a big help.

The people that run it down or simply do not believe in it, have never had it, but know its "bad"! I drove over 6 months and never felt the ABS working in my first car so fitted. I thought it was broken. On the advice of a colleague, I mashed the pedal on a wet day (road clear), the ABS worked perfectly.....

I have been a "convicted" ABS user ever since and it has got me cleanly out of several "situations" in the intervening years.

I (like many around the world) have been driving in cars with ABS since around 1995 or so......its like using safety belts, it/they are not perfect in ALL situations, but in most...The only time I ever needed a belt, though I always use it, was the day I accidentally tested my "Brake Assistant", in my last car. WOW!!!!!

REMEMBER you cannot pick your situation, they pick you!!!! (Though I sincerely believe that correct defensive driving reduces the numbers considerably. I have only had rear shunts since I learned to drive, 10 or 12 or so in 49 years of driving. No front end shunts at all, but one could happen tomorrow, I am getting old.....)

On my last car without ABS, I had to buy two new tyres after a full braking on the Autobahn north of Paris, flip flap, flip flap for 10 miles was enough......The rest of the two front tyres was like new.......a lot of wasted miles.

GA.

My apologies to you for not fully reading this earlier, (and for not giving you a GA earlier as well)

It is accurate, real world and to the point.

Many thanks for that.

I fully agree...I do this myself daily for about 5km of downhill run to work, and it does save gas. Engines will only stall if not at running at correct temperature, or below correct idling speed. All other causes of stalling can/ will happen 'on the run' in any event....

GA Sir Robin

I have done it many times; that is accelerating to avoid a crash. My reflexes are very good. I did some racing way back. There was an instance when traffic screamed to a halt. I always try to keep my distance, but this time, I had to jump the curb and go around the stoppage. In a split second, I was able to determine that no one was on the sidewalk before making my move.

But I agree with you that most people don't have the skill to accelerate/steer out of potential accidents.

Sorry to have to say this, but having to mount the curb to avoid someone stopping in front of you for any reason, still means you were either too close or simply not paying proper attention, or your car's brakes need some serious maintenance....

We have all done it at some point (been too close), anyone here who says different is a liar......

In the UK, the Government has for many, many years promoted a little ditty to help keep the right minimum distance, "Only a fool breaks the two second rule!". You start saying it as the vehicle ahead passes something fixed on the side of the road, you should have finished saying it BEFORE you pass the same thing. Its that simple and it works....

If you say this at a normal speed it takes about two seconds, which is the minimum distance in time that you should be behind ANY vehicle. It works for any speed of vehicles, provided they are driving at or around the same speed.

If the car in front is moving obviously far slower, then you need a greater distance than 2 seconds.....which is why I avoid the minimum and look for 3 to 5 seconds or even more.

It has stood me in good stead for nearly 50 years. Works great here in Germany where we still have some Autobahns with unlimited speed limits.

I have been hit in my car from behind around 12 times (never really counted) from other driver's cars/Trucks, always my brake lights were always in working order, as were my turn signals. Up to now I have not actually hit anyone in front (and not needed to drive over the pavement to achieve that!), though I am not so stupid as to completely rule out hitting a car in front before I pop my clogs!!!I am getting older (and more and more careful!)...

You were lucky that the pavement was clear........but don't think that you were in any way shape or form in the right, you were not. That was dangerous and wrong. Here, mounting the curb at ANY speed is an actionable offense, even when no one was there or injured......I don't know about the law where you are.

In your position, I would not have posted that on CR4.... I would have kept EXCEEDINGLY quiet!!

Have a great day.

'....If the car in front is moving obviously far slower, then you need a greater distance than 2 seconds......'

In theory, if you stay faithful to your 2 second lag, the car shouldn't be more at risk of being rear ended with reduced speed.... until the speed reduces to a stop...for 2 seconds.

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I Here in the US, higher speeds require a increased following delay for safety, but perhaps it is different in Germany, since you guys are on the metric system and all....

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I'm also assigning the nontranslatability of 'unlimited speed limits' to use of the metric system.

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I would appreciate some clarification on 'pop your clogs'??

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'....If the car in front is moving obviously far slower, then you need a greater distance than 2 seconds......'

In theory, if you stay faithful to your 2 second lag, the car shouldn't be more at risk of being rear ended with reduced speed.... until the speed reduces to a stop...for 2 seconds.

Even when I have managed to stop correctly, cars behind me that were too close have hit me. That has happened several times. The idiots behind are out of my area of responsibility by the way.....

I Here in the US, higher speeds require a increased following delay for safety, but perhaps it is different in Germany, since you guys are on the metric system and all....

Whether metric or not 2 seconds are still 2 seconds. You may not have understood completely what I was writing. The only reason I mentioned the autobahns is simply because we can legally drive as fast as we wish (assuming the car can achieve it!!). A bad accident here is pretty bad when high speed is involved.

I was once overtaken on the wrong side as I slowed down for a "JAM" and a big Merc sports thundered by, left the road and rolled 11 times (according to another eye witness in the jam), stopping aprox half a mile later....he was only badly shook up and could not stand up at first!! Really lucky....car was completely trashed.

I'm also assigning the nontranslatability of 'unlimited speed limits' to use of the metric system.

Wrong. Metric system is all over, except for a few countries, only Germany has unlimited speed limits as far as I am aware. The two are nothing to do with each other.

I would appreciate some clarification on 'pop your clogs'??

Dying.

Thanks.

BTW, I was joking about the metric system having anything to do with lag times.

Everybody can see that the seconds-minutes-hours-days-weeks-months time system is not metric.

When are you guys completing the change over to metric, and weening yourselves off the imperial time standard teet? What is the conversion again? 86.4 seconds in a milli-day?

As far as I am aware, most of the world is metric....Maybe you meant to ask someone else?

I found this:-

The United States is the only industrialised country that does not use the metric system as its official system of measurement, although the metric system has been officially sanctioned for use there since 1866.

Although the United Kingdom committed to officially adopting the metric system for many measurement applications, it is still not in universal use there and the customary imperial system is still in common and widespread use.

From here:- Metric system

By the way, most people in the UK under 70 can use either system, I do just that, the one that suits me at the time I use......no problems whatsoever. I can convert near enough in my head, that's not a trick, its quite simple, unless of course I need accuracy way past the decimal point.....Just remember 2.54!!!

Its a fact that the USA does not know its Imperial from its metric, which caused the crash of a Mars probe some years ago......expensive!!!

See here:-

http://articles.latimes.com/1999/oct/01/news/mn-17288

About time that a standard was set, for NASA at least!!!

Nope....you guys are only partially converted.,

You still measure time in units of seconds, minutes, and hours, right?

These have distinctly non metric characteristics.

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For complete conversion to metric, you'll need to start using measurements similar to millidays as a time unit.

....and how do you measure time?

How do you get to appointments at the right time made with someone using conventional time and calendar?

Oh, we're still on the Imperial system over here...

Is what you are saying that there was no thought or point to your post?

No. Quite the contrary. Allow me to point out examples of 'thought' and 'point' in my recent posts.

A modicum of thought went into corralling your misrepresentations of my comments. I was making it a point to prevent my comments from being distorted (no matter how tongue in cheek those comments may have been).

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The predictable development of your subsequent comments gave rise to thoughts about;

characteristics commonly associated with various nationalities;

the political appropriateness broaching such a subject;

and the ease with which such associations might be supported via anticdotal evidence, (for which the qualities of an individual might be arbitrarily assigned to an entire group).

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So I made it a point to see if anticdotal evidence was readily available that seemed to support a widely held, but not scientifically supported (AFAIK) addage concerning a specific nationality.

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It became readily apparent that there was no difficulty in finding anticdotal evidence supporting the old addage:

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"Germans have no sense of humor."

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It is important to prevent cognitive biases from influencing analysis toward the wrong conclusions....

For example, in this particular instance, there isn't enough information to conclude 'Germans lack a sense of humor'.

The evidence here is only indicative of

Andy_Germany lacking a sense of humor,

which may or may not be a common German trait.

Just as I thought, no serious point(s) whatsoever. How sad!!

Thanks for the clear up.

By the way, I am not German by birth. Most people here know from where I originally come from, without me having to actually tell them......

Germans, to my mind, have really only learnt modern world humour in the last 30 years or so, as an example, you should have seen their TV advertising before then, totally humourless......but today, they are 1000% better in that respect....

I sincerely believe that SAT TV has vastly improved the German Humour, possibly with help from UK (and other country's) TV programs that are now easily received here....also great programs on German TV from the USA and UK, mostly well translated, or shown with original language and subtitles.

Germany is my adopted land and I have lived here longer than I ever lived in the UK, or anywhere else for that matter.....but I have lived all over.....Man of the world? I believe so, at least more than most anyway.....

So many people feel they are world people, just because they stayed in their own country and watch National Geographic on pay TV (or whatever its called. I don't watch it by the way, I go [went] there and look[ed]!).......do you?

Or maybe you are also a world traveler, similar to myself, please let us know where you have visited and for how long.....

Some of the places I have visited for longer periods than say a month are:- Singapore in total around 3 years in 3 major visits, Hong Kong about 1 year in 5 visits, USA about 2 years or so in dozens of separate visits, South Africa in about 4 visits totaling about 4 months, Germany almost 32 years, but with also visits to other countries around the world, UK total about 25 years.

Shorter visits of a week or two, to Canada, Mexico, various countries in S.America, most Caribbic(Spelling?) countries and most Islands there, also Hawaii, Funafuti, Fiji, Ellis and Gilbert Islands, Australia (where I have a large family),Suez/canal, Egypt, Borneo, Bali, East and West Pakistan, India, Malaysia, Thailand, Burma, Bahrain, Panama/Canal, UAE, Aden, Gan, Lebanon, Cyprus, Greece, Yugoslavia both before and after the war, Austria, Italy, Luxemburg, France, Spain, Denmark, Norway, Finland, Russia, Sweden, Scotland (where my family springs from), Gibraltar, St.Helena, East & West Africa, Switzerland, Monaco, several other Indian Ocean Islands which I have forgotten the name of, Iceland, N.Ireland, Eire,Wales, Morroco to name but a few...I have actually seen New Zealand from the deck of a ship from a few miles away, but not had the time to visit!!

I have only just realized just how many places I have been over the last 60 odd years, impressed myself a little bit too!

Have a great day in spite of me!!!!

'.....

Just as I thought, no serious point(s) whatsoever. How sad!!

Thanks for the clear up.

By the way, I am not German by birth.

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Being German isn't about genetics, nor is it about geography of birth. If it were, then there would be little difference between being German and being French, for example, but that is obviously not the case.

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Being German has much more to do with language than geography or genetics (in spite of noteable attempts to make it more about genetics).

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As the conscious human brain has no underlying equivolent of a machine language, analyses are conducted in the available languages learned. Different languages vary in their suitability for certain analyses. It is an interesting quirk that while it is easy to point out analyses with which a language is particularly ill suited, it can be very difficult describe exceptional strenghts of certain analyses of a particular languaqe.

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For example:, Japanese only conjugates as past or non-past, so it isn't particularly well suited for saying (or therefore considering) "Now I rememeber thinking , 'by the time I see you next the the race will have been going on for 3 hours'".

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In a similar way, German thinking isn't fertile ground for humor. Humor often has a significant timing component, and my guess it that German sentence structure, though well adapted to things like Engineering, is severly handicapped when it comes to humor.

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So it should comeas no surprise to see the reaction:

'...no serious point(s) whatsoever.

How sad!!....'

You are obviously fluent in German and you are immersed German culture and language, but we can't be certain that your immersion and participation is responsible for your humor sense deficit. It is just as likely that you never had a keen sense of humor and that your move to and remain in Germany was at least partially motivated by the comfort you feel when surrounded by people who are similar to you.

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Whatever the case, you are one of my favorite commenters on CR4 and i have no desire to make you sad, so I will keep it on a serious note (as I have in this post) when addressing you, from now on.

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Enough of that. On to more interesting topics: travels and worldview.

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To begin with, I don't watch National Geographic TV. I don't have a TV in my house. I don't find it time well spent, so I choose to not participate.

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I have to admit, I am jealous of your travels. Mine are not as extensive on land, though at sea I might give you competition. I've been in the Arctic Ocean, Indian Ocean, North and South Pacific, as well as the North and South Atlantic Oceans. I have been to ever state in the US, except 6, and not counting stops that we're really too short to be meaningful, the only other places I've spent time are Canada, Mexico, St Croix, and Italy.

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I will take part of your advice and have a good day, but it won't be in spite of you.

.......I have to admit, I am jealous of your travels. Mine are not as extensive on land, though at sea I might give you competition.

I served in the RN, saw quite a lot of salty water, even a lot of fresh too while I was with them....

By the way, most of the rest of your post was actually boring and uninteresting to read, sorry about that......you have not changed my mind yet......

I appreciate your forthright attitude in both telling me directly that you distain my words. You are also clearly communicating that you allow very little room for things that don't fit your stolid ultra serious comfort zone. You seem proud that your mind remains unchanged; making your statement as much about your openness, as about my words.

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All of it is duly noted. While your mind remains unchanged, your words have convinced me to to modify my interactions with you, from this point forward, by adhering to the appropriate proverb:

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'Cast not pearls before swine.'

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(The following is my first attempt at developing a message specially tailored to an audience of your values and dialect....so please bare with me, but let me know if I'm getting it right or not.)

"Grunz! Gru-gru-gru-GRRRRRUUUUUNNNNNZ! Grunz. Grunz."

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At least your sense of humour has improved even though you "read me" again, really wrongly. Your problem, not mine........as you appear to suffer from the same problems that you perceive (wrongly!) in others......

Remember, you can lead a horse to water, but he must already know how to drink!!!! Some horses remain thirsty, but never ever notice it!!!

I showed you the water........

Your comment #68 suggests otherwise.

Grrrruuunnnnnzzz!

I can't resist stirring the pot a little....

If a (UK) Police Officer get's involved in a prang, they're in deep trouble. The philosophy is that there is no such thing as an unavoidable collision. Rather harsh, but even with somebody tailgating, the driver in front should be aware of what's behind them and take steps to avoid a potential 'accident'. Warning flash of brake lights/gradual slowing down/allow the **** to overtake, etc etc. A big light on top of the car helps, but defensive driving involves knowing what is behind as well as in front.

Like said, I may just be stirring the pot a little.

I flash the all round warning lights, it sometimes helps.

What you say is true by the way......

Ron,

You curb jumping /sidewalk driving story has convinced me that you are certain that you are among the most skilled drivers ever!

Twice in the same blog is excessive.

I know it is a good one, but to retain the effect it needs to be used sparingly.

Save it for those exceptionally deserving cases.....

Good post and great link, thanks.

The link in comment #65 is worth of being called 'great', but the link in comment #32 is not?

Andy, I think some un-Germanness is showing through, better go compose yourself, lest you betray something other than cold humorless logic dictating your actions.

Grunz! GRUNZ!!

You forget, your abrasive manner causes myself, and others, to gloss over your posts.....

If you were more agreeable, perhaps we might spend more time reading them.

Enough for now, no more answers, you are just a waste of time.....I am leaving this Flog Blog....Bye.

Getting too hot for you?

Aw, and the lovely smell of bacon wsa just beinning to become noticeable, but then you had to up and leave. Selfish, and downright swineheaded.

Grunz!

Do not do it you have much less control of the vehicle with no power or drag to the wheels and remember ( Safety First )

thanks to all of you who helped me learn a lot with your experiences. keep posting

thanks

I have coasted vehicles for the past 40 years, shifting to neutral (not turning the engine off). Some pickups have so much rolling friction, it is like pressing on the brake pedal. The best rolling vehicle ever was a 1990 Oldsmobile Park Avenue, it just rolled and rolled and rolled; around town mileage was about 26mpg, over-the-road mileage was 32.5 without coasting and 37 with coasting.

My current 2010 Toyota Highlander gets 24.5mpg without coasting. It get 31.3 with coasting.

I sell my vehicles to college kids when they're worn out at 300K+, and I've never had to service a transmission, other than my wife's foolish purchase of a Dodge Caravan minivan, which was known to have crippled transmissions off the showroom floor.

For 10% increase in gas mileage, I'll put on an extra set of front brake pads over the life of a vehicle that does 300k. Maybe others won't, it's up to the individual.

If you are interested in saving fuel (in a way that doesn't damage the car), there is a lot more you can do if the car has a manual transmission than if not. The following comments concern a non-hybrid (no regenerative braking) vehicle with a manual transmission.

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To begin with, you don't have to coast in neutral, just with the clutch depressed.

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Significant efficiency gains are available in minimizing total use of braking (by engine or by regular brakes. At first this may sound like I must own a auto body repair facility, but this isn't about never braking. This is about timing your braking to allow the highest minimum speed.

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Every MPH or KPH reduction caused by braking, will require additional fuel to once again regain that speed.

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By braking typically earlier than is the norm for a red light and then coasting, it is often possible to maintain a minimum speed through the light eliminating a complete stop. With some practice, consideration for the number and type of vehicles at the light, and learning to watch clues like crosswalk lights and cross traffic patterns, a complete stop is rarely necessary.

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Where and when it is safe, in certain vehicles, if you have a long coast, you can briefly position the ignition key to shut off the engine, then return it to the run position, thereby coasting with the engine off. When it is once again time to accelerate, briefly release then depress the clutch to start the engine, then engage and drive as normal.

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Here is a discussion concerning BSFC maps and Pulse and Glide techniques.

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My average fuel consumption in a lightly modified TDI Jetta with conservative use of these techniques is around 52 mpg in mixed mostly city driving, and 61 mpg on long trips.

I doubt I have my clutch depressed as long as if I were a normal driver waiting at the stop light, but I looked into it, and it appears I should shift into neutral there as well.

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Thank you for the heads-up. I appreciate it.

I'm not a frequent driver, so this will probably get me a right telling off; Isn't option 3 to change down gears using the engine as a brake ? Probably doesn't do the transmission much good, and brakes are 'sacrificial' components to be used as such, but all the same...It keeps you with some power, and hopefully in a useful gear ratio to accelerate if something nasty happens. When I'm nearly stopped at the lights I wouldn't want to be in top gear.

Like said, I don't drive that often, so such things as double-clutching elude me. A lot of people just drive 1-3-5, though I feel compelled to ride the lot (unless I'm in a hurry to stop).

That does not save on fuel, in fact it may increase consumption in most cases.

Also brakes are cheaper to replace than clutches and transmissions.....

GA there too. My dad always said (in reference to down-shifting), what would you rather replace, brake pads or the clutch? Took me about a millisecond to process that one. (Especially since we were driving front wheel drive cars, whose clutches are no fun to replace. )

Maybe it's just me...and I do consider myself somewhat of a "car guy"...I know the speeds at which I need to engage my clutch based on my vehicle's speed. I set the rpm of my engine to match so that when the clutch engages there is little difference in speed between the engine and the tranny. It makes for a much smoother shift and decreases wear on the clutch.

If the driver just jams the car into gear each time without consider the clutch then there is unnecessary wear and tear. I see people do this when I ride with them and I cringe when I see them slowing the car by slowly letting out the clutch with zero input on the throttle.

Oh, but I do coast from time to time...and then match the speed before shifting back into gear.

I do RPM matching up and down because it makes it easier on the synchros. On my '87 Jetta about ten years ago, the clutch lever inside the tranny split at the splines. I thought the cable broke at the time. I drove it home about six or seven miles, and eight stop lights. What I found was that it was happier to start in second gear, because in first it bucked like crazy. Second was tall enough that you had to crank it longer but it accelerated smoother.

Shifting without a clutch was surprisingly easy and very smooth once you figured out the shift points (I already knew them pretty well since I had already driven the car 150K), and the key to pulling out of one gear is to "unload" the gears slightly by lifting the throttle just a tad. Making slow throttle changes so the RPM's are changing slowly make dropping it into the next gear easy. Maintain just slight tension of the selector and it will pop right in, smoother than using a clutch.

My truck driving friends hardly ever use a clutch. My understanding is that truck transmissions don't have synchros so they either shift without the clutch when they can do the RPM matching or they have to double-clutch when they change gears. I'm sure someone on this forum can shed more light on this than me.

Cheers !

I had a '80 Celica that would shift beautifully with no clutch. When the slave cylinder died I had to do this for two weeks. It really wasn't that bad. I got so I could make a jack rabbit start from a red light into first gear without shutting off the engine.

Reverse required starting in gear, so I would seek out pull through parking spots.

When going downhill in the mountains, it is often essential to use the engine's compression as a brake, by down-shifting. Otherwise, the brakes can (will) overheat to the point of danger. I remember seeing a forest fire that was begun by a flat-lander who was pulling a trailer as he exited Kings Canyon National Park in California. As he pulled up to the ranger station, the severely overheated rear tires exploded in flames and there was nothing the ranger only a few feet away could do. Truckers in mountains will routinely down-shift. The rule of thumb is to use the same gear to go downhill as you had to use to go that hill.

If, however, the road allows the vehicle to speed up, then using the engine to keep a slower speed can frequently be minimized or eliminated. I crossed Colorado in my anemically-powered Geo Metro and couldn't get over 35 mph on the uphills but easily coasted to 85 on the downhills (in neutral with the engine still idling).

--JMM

Why stop there? Why not turn the engine off when the car isn't accelerating?

There is a strong argument for this from a fuel efficiency perspective. It is what basically drives the large efficiency gains available from pulse and glide.

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Automobile engine, especially typical gasoline engines, have abysmal performance at low partial throttle, as compare to efficiency when driven at near wide open throttle. Much of the inefficiency at low partial throttle can be attributed to pumping losses.

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Running the engine at its most efficient produces an efficient pulse, cutting off the engine and maximizing the glide provides an efficient way to deal with the mismatch between what is delivered when the engine is running most efficiently, and what is needed at the moment.

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There are vehicle specific safety implication that should be well understood prior to using any pulse and glide technique.

Thanks for the Wiki link. Unfortunately, we see way too much of this across the entire spectrum. Confidence is good, but it must be tempered with a sense of humility.

<...There are vehicle specific safety implication that should be well understood prior to using any pulse and glide technique....>

...which is why this practice is not taught for the purposes of passing a Driving Test. Its impact on other road users is a potential minefield.

'...Its impact on other road users is a potential minefield....'

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Quite right. inescapably, the impact on other road users whenever we drive a car on public roads is a potential minefield.

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You are exactly right, in that this should not be taught to new inexperienced drivers.

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It is a powerful tool for enhancing efficiency. Like most powerful tools, improper/unsafe use can pose unacceptable risks to self and others.

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That said, (and with recognition of the potential for bias inherent in self-evaluation) my own driving habits and driving record present a very low risk of contributing to any accidents.

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Driving to (safely) maximize economy, I extremely mindful of my surroundings. I am not mulling over past conversations nor rehearsing expected conversation (though I can certainly be caught doing this at other points in the day). I do not make or receive phone calls or text message. I do not drive at unsafe speeds, and I plan far in advance to minimize sudden or hard braking.

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I would guess my habits are similar to many people who engage in hypermiling. I would argue that the typical hypermiler's attentive but nonstandard driving habits present far lower risks for everyone than the very large group of drivers that are either hell bent on racing to squeeze up one more space before the next light or can't be bothered to pay as much attention to the road as they are to their phone.

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Pretty much every drive I make, I observe at least one (usually more) drivers tailgating at an extremely close unsafe distance. Typically they are either visibly agitated at the vehicle in front of them, or they are barely paying attention to the road.

I would guess it to be the most common obviously unnecessarily risky behavior.

I can guarantee that none of those ever-present, traveling hazards is a hypermiler. (hypermiling and tailgating are mutually exclusive).

< (hypermiling and tailgating are mutually exclusive). >

So if a hypermiler is riding your a$$ he is only "drafting" !

If he is 'riding your a$$' he isn't hypermiling.

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In tailgating, the frequent need to brake, sometimes heavily, in most cases is not going to improve efficiency.

Two likely exceptions would be:

-There is probably a safe distance behind a fully loaded tractor trailer at which you gain some benefit in reduced average drag without incurring significant additional risk of an accident. Much reduced drag is possible at unsafe trailing distances, but depending on the prevalence of highway patrol, as well as any monetary value you place on life and well being of yourself and those in your automobile and possibly those traveling nearby, it is unlikely to be economically advantageous investment.

-It is possible for two or more vehicles to travel together at distances close enough to gain efficiency without significant increases in risk, with the implementation of a system with sufficient of communication and control.

i will support option no 2 it will give no harm to car.