1998 Pathfinder - Rear End Noise

Try looking at your rear brakes. Are they disc brakes? Then I don't know. However, if they are drum brakes, then it sounds like one of the brake shoes are dropping back, as you come to a stop. The vehicle doesn't actually move forward, correct? Also, do you have a manual transmission. If so, when the vehicle comes to a complete stop, there is no force being applied to the rear axle at all. Then the brake shoe that is hung up on the inside of the brake drum drops down and you hear the clank.

One way to solve this problem is to make sure that the self-adjusting brake mechanism has a chance to work. To do so, you must put the vehicle in reverse and apply the brakes. But you need to do this four of five times, over a distance of thirty or forty feet, say an empty parking lot. During the braking, while in reverse, the brakes have a mechanism to move the brake shoes up closer to the drum, since the material wears out and creates a gap.

Now, if this has not been done for awhile, say you seldom back up in this manner, then the mechanism itself may be stuck. It's a couple of simple metal parts which can accumulate dirt and then rust fairly easily. You can tell a lot by pulling the brake drum off.

Good luck.

You really need to check ALL the rubber joints. However I would start by checking your shock absorber rubbers AND ENSURE THE MOUNTING BOLTS ARE TIGHT! As this is the most common cause of your complaint. Before you start though test drive with the jack and spare and all the other tools and things out of the car. Often a loosely mounted jack will bang when you come to a stop.

When checking the rubber bushings look for wear and ensure the rubber contacts both inside and outside and is physically still stuck to the metal. Try sliding the component along the bolt line. If it moves the inside tube has torn out. Also check the outside of the bush and ensure its carrier is not oval, bad wear can result in the eye becoming slightly oval so the new bush only contacts partially allowing the rod to move about.

Dud shock absorbers (dampers) can also bang when you stop if they are badly worn

Thanks for the ideas so far. I will check the brakes, however I am sure it's not a loose jack or anything of that sort. I swear I can hear and feel the rear axle come up under me and thud. I just recently bought the car to use for utility, but it came with receipts for rear shocks less than a year old. I doubt it's that, besides it passes the bounce test. There is no noise when driving, just when coming to a complete stop, and even that can be controlled by letting off the brake slightly just before momentum stop. I have also noticed that is is hard to duplicate in back to back trials. After it does it, I can move forward and slam the brakes without causing the thud again. But, after driving a bit and trying to stop it comes back.

The rear brakes are drums and it's a 4x4 with rwd, automatic tranny. When I replaced the lower arms, there was severe deterioration to the bushings. I knew this was the case because of the side to side swaying, and just assumed it caused the thud as well.

Here's some more detail; The vehicle has coil springs with double trailing arms. The lowers are connected to a bracket also supporting the rear shocks in the back and to the frame in the front. The rear shocks sit at a severe angle horizontally, so I thought of that too, but they tested OK. The uppers are connected to the rear axle in the back and the frame in the front. Other than that there is only a thin stailizer bar and links and a pan hard rod which runs diagonally and left to right in the back.

The more I think about it the more inclined I am to narrow it down to 1 of 3 things; Either the upper arms are worn badly and cause the rear to drift forward. Maybe this also caused the sever wear in the lower arms bushings. Maybe, it is the brakes as one of you suggested. Or maybe I have a problem somewhere along the driveshaft which gives when momentum comes to a halt. I'm thinking a loose joint or something that allows too much play.

The only way to check the shocks is to lift the vehicle in the back. You won't be able to move any of the connect points in the chassis unless it's jacked up and on jack stands under the frame rails. Then check chassis points, and transmission bushings. Odds are that it is something that has been worked on recently. I bet its a loose shock mount, had the same problem on my Jeep. Hope this helps.

Welcom to the forum.

Your proble is the upper arms I too had the death sway and thud and just replaced the lower arm and the thud persisted until I changed the upper arms.

Good morning all.Another possibility is the bearings and/or shims in the rear end itself.You may need to pull the cover off and check the play to factory specs.

From completely out in left field.......does it do it more or less when you have a full or empty gas tank?

Heh heh, I was just thinking the same thing.

I had a 1991 Oldsmobile Silhouette that "clunked" when the tank got less than about 3/4 full but stopped when the tank was below about 1/4. Turns out these early GM mini-vans didn't have baffles in the plastic fuel tank. It was not only audible but could be felt physically as well.

GM put baffles in on later models.

Hooker

Reminds me of a tanker truck I drove back in High school days, 3000 gallons of home heating oil, no baffles, winter stopping took some planning.

I'm not sure about this but I have a chevy truck and it has a similar situation. What I have noticed is that the rear end suspension is leaf springs, and do to motion and or torque they have a tendancy allow enough motion for the springs to rock such that like the rear shackle/leaf spring support bracket or the front rock, thus making this noise.

I hope this helps you.

Brian

Not U joints from the sound of it.

Have you ever replaced the shock absorbers?

Dead shocks are one of the causes of death wobble as well as warn bushings, which are hard to diagnose unless the shaft is removed, just pulling on one is not a good test, unless of course you weigh as much as the truck itself.

To check the wheel bearings, jack up one wheel at a time, pull on the top of the tire, should be no appreciable movement.

Good luck.

OK, so here's what I've found so far;

I tried the setting of the rear brakes by backing up repeatedly and stopping. No help.

I checked everything underneath, spare tire, etc. and nothing is bouncing around.

I DID find something very interesting though. It doesn't happen when I'm in Neutral, only in gear. I can get the vehicle up to speed, shift to Neutral, then stop, and it's all fine. However, if I'm in gear forward or reverse, I get the bang foward just as I come to a stop, or immediately after coming to a stop.

Now I'm thinking it's a tranny issue. Maybe its a hard and late downshift? But, that wouldn't be the case in reverse, as there's only 1 reverse gear, right? I have also noticed that when turning onto my street which is a hill going up, it takes a second before the tranny shifts down. Consequently, it feels sluggish for a second, and then picks up again. But, maybe it's not the shifting that is delayed, but rather the engaging of the driveshaft.

Axle issue? Drive shaft? Now I'm starting to get worried. It appears it's not something simple like bushings, or it would occur no matter what gear I was in.

Any ideas?

First the noise thing, crawl under the truck and check for cracked rubber mounts at the transmission and the motor.

you might also enlist the help of a friend or family member to sit in the back of the truck and help to determine exactly where the noise is coming from.

As for the shifting issue, first pull out the transmission dip stick and give the fluid a sniff, if it smells burned your clutches are burned and require replacing. No burned smell, take it in for a new filter and fluid, a transmission tuneup can make a world of difference.

Once you nail down the area of the noise I will be glad to make another guess for you.

MMM it is sounding very transmission like, though I would grab each shock and turn them left and right to ensure the rubbers are working first. Your story is precisely what a poorly tightened but good shock absorber will do.

sounds like the transmission might be dragging. more modern units change out of gear when you stop, if the engine idle is too high it will hold longer and let go when the car finally comes to rest, giving the thump sound as the gears let go. Check your Engine and Transmission mounts, particularly the transmission mount point as the same reasoning applies to them. The transmission pushes one way (normally up) on deceleration and drops when the load dies, causing your bump noise.

Of course it goes without saying that you have cleaned the car underneath to a high standard so you can actually see the components not just the grime on top!

Car is fairly clean, all components are visible. Well, as visible as can be on a Nissan. They tend to jam alot of things in to very tight quarters.

The idle is good (700 - 800 rpm). The tranny mount sounds promising. Especially since (and, I didn't mention this before) my VSS just recently started malfuntioning and set off the SEL. I know that the speed sensor on these is located on top of the tranny. A bad mount on the tranny would possibly explain both problems. The tranny banging up would likely damage the VSS. And it would also explain the lack of banging when in neutral.

Thanks for the brainstorming. I'll definitely check it out.

Some vehicles have a two section drive shaft divided by a mechanical bearing of sorts this joint if worn could produce the symptoms you've described.

While you are under the vehicle checking the trans mounts and center bearing, take a look at the trans corssmember, where it should be tight against the frame. Good luck.

I couldn't find anything that looked horribly wrong.

One question though; should I be able to move the tranny up with a screwdriver wedged by the mount? It's hard to see the complete rubber mount without removing the crossmember, but I can pry a screwdriver on on side and easily lift up the whole tranny off the mount. The mount feels really quite soft.

Again, the rubber doesn't show any damage, but perhaps this is an indication of a worn mount? I would think that it should put enough upward pressure on the tranny that it wouldn't be able to move so easily like that.

In the back, the upper arms look good and tight, the shocks are pretty tight. I can get slight rotation on them, but feel the bushings pulling back tightly, no lateral movement. I DID notice serious wear in the stabilizer bar bushings. There's probably a good 1/8 inch of gap inside. I can slide the whole bar around pretty good with just a bit of pressure. However, I can't see this causing the knocking sound. I'll have replace these, as well as the front.

I test drove again, and really felt and listened for everything. The bang is the same as I get when shifting from 1st to second. A hard shift really. It doesn't feel outrageous, I just know I shouldn't feel it when stopping. Sometimes when the bang doesn't happen as I stop. It happens, as I take off again. Sometimes it's a double bang. I tried it in each gear, and there's no change. Does the transmission have a separate gear that it shifts into other than 1st, when you stop? Or perhaps a momentary disengagement of the shaft? I thought if it was a hard downshift, I could do it in '1' and not get it, but it still happens. So, I believe it's the transmission shifting that's causing it. Whether it's the tranny itself, or something peripheral is the question. I guess it should be easy enough to get a new mount and replace it, just to see if that's it. Maybe a tranny fluid change should be in order as well.

I guess I'll just use a process of elimination starting with the easiest first.

Simple answer, no transmission should not move.

It does sound like you have a mount going south on you, they are inexpensive and easy to replace. Just sort of fiddly to do, be sure to support the transmission when you remove the cross member.

I had the same problem and my drive shaft bolts were loose.

Thanks Guest,

Was your problem with a Pathfinder as well. And if so, could you specify exactly what drive shaft bolts?

I haven't been able to replace the mount as it hasn't gotten above freezing here in weeks.

But, I can certainly take a look at the driveshaft just by sliding under the vehicle. What should I look for? Are they loosened nuts or bolts? Or both? And exactly where?

Thanks for the help.

The trick to checking looseness in a driveshaft, is to allow it to rotate on one end only. Chock the wheels both in front and behind the wheel. Then place the transmission in neutral, and lock up the parking brake. Then go under the truck, and rotate the driveshaft in back and forth manor. There will be some free movement, or backlash between the splines on the axle shaft and the axle side gears, between the side gears and the spider gears, between the spider gears and the differential housing, and between the ring gear and the pinion gear. There is no way for you to know how much play is in any of these components. but that does not matter at this point. You are looking for movement between the driveshaft, and the flange that is bolted to the rear pinion gear shaft. If there is any movement at all it is a worn part, or a loose set of bolts. That you will have to see for your self, we can not do that for you. Good luck. Let us know.

Thanks for all the detail Bob. I'll slide under there today before the snow comes. I still think the tranny mount is the real issue, but if this person had another similar year Pathfinder, there could be something to it.

I just wish we could get a couple of decent days here in the NE so I could get some of it done.

I've got a "99 model Pathfinder. After investigating a very similar complaint, I found that after replacing the rear shock absorbers, the upper passenger side nut would not seat properly. This allowed front/back side/side movement to occur. I shimmed the space with an appropriate flat washer and the clunking pattern was erased.

Regards

OK, been under the car again. I can't find any detectable looseness in the driveshaft or shocks or bolts anywhere. I even laid down under the vehicle and rocked the rear at least 5-6 inches up and down, trying to find something. But the only thing that seemed unusal was some large spring directly in front of the rear. I have no idea what this is, but it expands and compresses with up and down movement. It is attached to some sort of bracket. It's abut 6 inches long and 2 inches in diameter.

Another bit of evidence; I could not duplicate the banging noise until the car was run for quite a while, and then it was faint. After a good 30 minutes of driving, it came back as usual. What could this mean? I'm thinking it brings me back to the tranny mount. The rubber hardens when cold, but when it warms up under the vehicle, it softens again? Of course this could be true for any other rubber bushing in and around the rear suspension as well.

And, OK, I may be embarrassing myself here, but I also noticed something really strange at the front. The front driveshaft pretty much spins freely. So, I jacked up the front end and turned the wheels one at a time. Each one made the shaft spin. But, when turning the right wheel, the left wheel turned in reverse at about half the speed. Turning the left wheel did not cause any movement in the right. Is this normal? The differential was NOT locked.

I'm really frustrated at this point. I'm considering just going to the dealer. I'd bring it to an indie, but they usually just replace things one at a time until they get lucky and find the problem $1000 later. I really wish I could figure this thing out.

Ok. The front drive shaft spins freely because there is locking hubs in the front axle. This is to save wear and tare on the front axle and save gas mileage. The tire spinning in the reverse direction is from the differential action of the front axle. When a vehicle drives around a corner, the outside tire covers a larger distance than the inside tire. If there was not some method to allow for this, your tires would slip on every turn. There is also another differential in the transfer case, to allow for the different distances that the front tires will cover in a turn also. Don't worry about the findings in the front.

SHOCK

duh!

I have the same SUV with exact same problem.

Have you ever found the cause of this problem?

thanks

Tom

Hi Guest,

I had not found the problem, until something happened by accident....I heard a rattling under the car and upon inspection, found that a rustyexhaust hanger had broken loose. I cut it off and replaced it with a new one. I tightened everything nicely. After a few days, I realized the banging was gone. Obviously, it was a loose exhaust. It still doesn't explain everything, like why it didn't happen in neutral, but it went away nonetheless. I couldn't imagine that an exhaust could make such a hard a loud thump, but it apparently did.

One thing you should know about these cars; they ALL get the death wobble, every single one of them. This is caused by a bad bushing in one or both of the rear control arms on each side. (4 total) They don't just wear, they completely tear through the middle, leaving you with about 1/2 inch of play in all directions. You can not see them without removing the control arms, and these are really a bear to get off. When I had mine removed, the whole rear shot backward about 6 inches. Had I been under the car and in the wrong spot, I wouldn't be here to write this today. I wouldn't attempt it myself. But if you have any kind of rear end banging or wobbling, and more than 50K miles, I would do this first. It's a guaranteed problem on all Pathfinders from 96-2004.

Thanks for the info, I'm going to check it ,even though the whole exhaust was changed couple months ago .

I have the exact same noise and movement in my rear end 96 Pathfinder. I have checked and replaced everything, upper and lower bushings, shocks, sway bar rubbers, universals, exhaust and it still does this. I can't believe some else has the exact same noise and movement. I have been wrenching for years and always figured myself handy with any kind of car or truck but this has me stumped. Only thing I havn't done is removed drums and checked to see if the brakes etc are working properly. Darren

I believe it is transmission problem ( this bang disappears when shifting to neutral before stopping).

Tom