2010 Ford F150 4X4 Rear End Noise while Turning

Just about all Ford limited slip differentials require a friction modifier added to the differential lubricant to prevent the problem your vehicle seems to have. The container consists of 5 or 6 ounces and is normally added to the differential lube. I believe the modifier is available at most auto supply stores in case you can't get to a Ford dealer to purchase it. Usually we just add it to the differential and it takes care of the noise problem.

h

Hey great idea H,

I will look into this!

Thanks

I'd be checking the oil level in the differential to make sure its to the mark.

One of the "service" tricks is to take the vehicle to a large vacant parking lot. Drive in a hard right hand circle slowly ten times.

Then drive slowly in a left hand circle ten times. At the end of the procedure drive forward for 100metres/yards. Job done.

This procedure, pushes the oil in between the plates. At least thats how it was explained to me.

I've used this proceedure in a couple of LSD equipped Fords that I've owned to quiet the LSD chatter in the differential.

Toburgrynbak,

I just left the only auto parts store in the area (NAPA) and they did not have any Ford specified friction modifier that guest "h" suggested so I will try your service "trick" next. There is plenty of flat level areas at the plant that I am working this week.

Thanks and I will keep updating this thread.

I have an SUV with a limited slip differential too. I just changed the lubricant in the rear end last year but can no longer get the correct spec. additive (Isuzu) - although it should be at all GM dealers. Anyway, after much searching, I ended up using the same product as used on GM full-size pickups with limited slip. It worked very well.

I am not suggesting that that you buy the same GM additive but I suspect that these additives are similar. If you are in a bind (no pun intended) you could get something close to Ford spec. but maybe not exactly the same.

Your vehicle manual will also specify the correct amount - usually 4 to 8 ounces. Maybe try a little less (50%) as this is not a normal replacement of the differential fluid and some factory additive may still be present.

Any spring loaded clutch design locking differential could have this happen to it. But I have only experienced it on Ford products. The worst offender was a small fire truck F350 with a Dana 80HD. It banged so hard the drivers refused to drive it one weekend. The remedy was to drive it in circles. First clockwise, them counter-clockwise.

The problem stems from the lubricant between the clutch plates working it's way out. Without the lube, the clutch plates will chatter when forced to slide against each other. By turning in circles the clutches are forced to spread apart when turning. This will allow lube back in between the plates again. If you run the diff level a little higher, it might help keep the plates lubed. It can't hurt. Good luck. Do the circles. If it improves, don't worry about it. If not, be sure to notify your Ford dealer. If they tell you to drive it, it will be covered. If they tell you to tow it, they become responsible for the cost of the tow. Let us know.

Are you sure you have the right tyre pressure? It sounds far too high to me.....

Can anyone confirm/deny this thought!

I don't think it has much to do with your main problem.....but if the pressure is as off as I think, it could change the handling characteristics of the truck in a dangerous manner......possibly.....

Hi Andy,

I don't think the tyre pressure is a problem, in our work ute, a Dual Cab Toyota, we put about 70 psi in its tyres. In our Port Lincoln campus, they have the same type of ute,and the campus manager over there knows all (or at least he thinks he does.

Once when I was over there working he was bitching about how useless the ute was. I said I would take it for a drive...........went to the servo..........tyre pressure check 36psi. I put it up to 70psi and took it back.

His remark was "shit, that's better how did you do that"..........I showed him the tyre pressure on the side wall.............When all else fails read the instructions.........he had nearly stuffed a set of Coopers by running them at too low a pressure.

Hey Andy,

Yes the tire pressure is OK. Tires are rated for 80 PSI. I run at 70PSI because the ride is horrible at 80PSI.

Thanks!

What does Ford recommend for the vehicle. Thats the value that needs to be used.

I do agree that the "fully loaded" pressure usually improves the driving and reduces wear and heating, thats what I have done for almost 50 years.....

The pressure marked on the side of US tyres is not always relative to the required pressure from the vehicle manufacturer, its more to do with what the tyre can actually handle.....

In Europe at least, over/under pressure might be noted by the police and they would issue a ticket. US laws are probably laxer....

The first thing I would try is driving in a tight circle in a vacant parking lot, to the left and then to the right, about ten full circles. The clutches get dry sometimes, and this helps. more than likely, this will solve it. on the other hand, ... It's possible someone at some point had the truck's rearend serviced, and they refilled it with the wrong gear oil. The posi trac rearends use a different hypoid gear oil than the plain limited-slip differentials use. Use of the wrong oil can make them shudder, groan, and/or stick while driving in low traction situations, such as wet or icey pavement. Even with this condition, as long as it's full of any kind of oil, it's just a nuisance problem and will go away as soon as the oil is changed. If it was run dry of oil (why it was serviced) then you may have worn clutches in the rearend (posi only).

If it's NOT a posi-trac, then your carrier bearings aren't adjusted right, and when you turn, the outer axle is pushing in a tiny bit on the carrier and hard meshing on the pinion gear. A clue that this is happening is that it only happens when you turn to the right. This can destroy the ring teeth and pinion gear. (Another clue that this is happening, is a leak at the pinion gear shaft seal. It starts to leak after a long time with this problem) It takes a long time to ruin then usually, and if you don't hear metal to metal in the straight aways under load, then you should make it home, even 500 miles. (You will be able to hear it roar long before it goes out) Take the plug out and stick a magnetic pick-up stick down nto the bottom of the oil resevoir in the differential and pull it out, looking for metal shavings. No metal? You are good to make it home. It's also a good idea to check the temperature of the pumpkin(diferential housing) once or twice while driving if you are pulling a heavy load. if you see smoke coming off the housing surface, it's way to hot and already ruined inside. If it's too hot to touch with bare hands, it's got a serious problem inside, but not yet ruined. If you can just barely keep your hand on it, it's fine.

Good Morning All,

Thank you all for the comments and suggestions. I tried driving in left/right circles last night. This seemed to alleviate the problem but did not eliminate it. I just called the local NAPA and the man said that he could order the Ford spec friction modifier for me this morning and would have it tomorrow.

I will ad the modifier and try driving in circles again and see what happens.

Thank you all again for the help.

If you post this on a Ford truck forum I'm sure they will point the finger at your LSD. I've got an F350 w/LSD and I get the same growl when turning. The clutch packs rapidly stick and release creating this vibration. I've changed the fluid and it didn't improve. From what people say in the truck forums, it won't hurt anything. The only solution appears to replace the LSD with an aftermarket one.

IMO, it may be possible to eliminate the sticking clutch packs by using a gear oil without the friction modifier to make the oil more slippery. However, this will defeat the purpose of having limited slip.

On edit, I noticed you truck is 2010. Feel free to go bother your dealer. If their not a bunch of lazy SOB's, I'm sure they won't mind the work.

"Friction Modifier" means it makes the lube a bit more slippery. Ford LSD's in particular had clutch plate chatter which is why they came up with the modifier to get them to slip a bit. Add to much and you won't have much if any limited slip to it. Just slippage.

Good to know, I figured LSD friction modifier was similar to that used with motorcycles. With motorcycles that use wet clutches, "friction modifier" is used to add friction so the clutch packs have zero slip.

There is a good possibility that you need an additive that Ford has for the clutches in the limited slip differential. I had this problem with a mustang and it was easily solved. Apparently in some cases the clutch disc's will swell and this will keep limited slip engaged similar to a spool and the chatter is the slipping on turning.

Hey Bob,

Thanks for the part number and the offer for the bottle that you have.

I would like nothing more than a trip to sunny Florida. Hell after the winter I have had, I would consider a move down there permanently but I will have to take a pass on your offer this time.

KJK

Again, thanks to all that responded and commented. This certainly has been a learning experience for me!

I feel better about my trip home and (hopefully) the rear end not self destructing on the way.

The truck will be in my local Ford dealer for warranty service first thing Monday morning.

I will post back here when it is all said and done and give the final out come.

Does your truck require a service to be performed on the drive axles at a mileage that you have passed? If so, they could refuse to honor the warranty because you have not maintained it in accordance with the requirements of the warranty. If your owner's manual says that you are required to service the drive axles, You could have a local service facility perform the service for under $60 per axle. that would force Ford into honoring the warranty. It would be better to check on this before surrendering your truck to them. I had a co worker who had a brake pull problem in his Dodge truck. Because brakes are not a warranty item, he paid for the repair. The cause of the rtepair was axle fluid leaking past a rear axle seal onto the brakes. When the rear end started to make howling noises, he went back to the dealer for warrenty work. They declined it because the axel seal was not replaced according to factory design. ( an improved seal design) He wound up purchasing a complete axel assembly from dodge. $$$$ Good luck.

bob c,

Excellent point, thanks for the heads up.

I will check the service manual before I involve Ford.

Thanks again!

I assume that you are not driving in 4 wheel drive on dry pavement. When we used to get a problem like that at dealerships, we were told by the factory to take the vehicle to a parking lot and drive in circles 4 or 5 times in each direction. Doing that gets the lube on the clutches. It is making the noise because the clutches are dry. Try it.

Nope, don't drive in 4X4 on dry surfaces. As suggested I did try driving in circles, this improved the symptoms but did not eliminate the problem.

My major concern was driving another 500 miles to get back home to take it into my local dealer which thanks to all the input I have received here, I don't think will be a problem.

It is still under warranty so we should be OK.

Thanks for stopping in and offering you suggestion, much appreciated!

UPDATE - Last night I added 8oz of Ford friction modifier (drained a few ounces first) and drove in clockwise/counter clockwise circles.

I drove around and put on about 12 mile and the noise was gone.

This morning while driving to the job, the noise came and went a few times but was no where near as apparent as it has been.

I am still taking it into my local dealer when I get home this weekend.

PS bob c - I checked the maintenance schedule, no rear end service required for quite some time.

Thanks again to all!!!!!!

Here is an interesting link to a discussion on the F150 LS differential problem ... http://www.fordf150.net/forums/viewtopic.php?t=76029

The owner was on his 3rd warranty trip to the dealer for the problem at 70k miles.

awelch,

Excellent link. I had been on the fordf150 web-site already but missed this particular thread. There is some great info there.

Being that I have a 100K warranty, I will take advantage of it and let Ford deal with the problem. I will however investigate the after market solutions discussed on the link.

Sounds like this is a chronic problem with the Ford LS rear end.

Thanks again - KJK/USA

Final Update

Dropped off the truck Saturday morning (got in early), picked up the truck late last night. Clutch pack was worn and replaced.

This morning, I put on 70 highway miles and 20 city miles, stop and go, turns, ect. Not a single groan!

I am so happy there are no more strange noises coming from my rear end.

Thank you all again for your help!!!!

Good to hear. The disturbing thing is that it essentially wore out prematurely at 37,000 miles. There must have been an assembly or material flaw.

I agree, either improperly assembled or defective clutch packs. I think Ford techs can be a little shifty when it comes to listing out reasons for failure. Ford can't improve upon their problems without properly documented reasons of failure.

On a recent turbo failure I had, they listed the reason as "Turbo went oblong" whatever that means. In reality the variable geometry unison ring froze in place due to corrosion. This is a common issue that could be easily resolved only if they made certain parts out of stainless. Also, my truck is an '05 and I've been living with a noisy LSD along with many others since new. IMO, if Ford identified the root cause back then this wouldn't be an issue on 2010+ vehicles.