Automotive Question - Noises from the Rear End

[rtimgray]

Well, at least I prefaced the title with it being auto-related. I was just going to ask about "Strange Noises coming from my rear end".

Anyway, I've got a 1996 Isuzu Rodeo (same as a Honda Passport of the same vintage). In the last year or so, I've been getting a "thumping" noise that sounds like its coming from the back of the vehicle.

Bascially, when I make a turn, I get a "thump". It almost always happens when at a higher speed - and I mean like when I'm turning off a main road onto a side road at, like, 20 mph and its a 90 degree turn.

I also get a lot of creaking and groaning in an off-camber situation. When I turn off of a street into a parking lot that has an incline/decline apron, I get loud groans and creaks.

It seems to me like it is probably a suspension-related item, but I can't find anything out of whack. I replaced the bump stops in the fall - one had almost dry rotted off and was barely hanging on and the other one fell off when I grabbed it.

I don't see any kind of shiny areas that indicated something sliding back and forth or rubbing or anything like that. The shackle bolts and bolts at the leaf spring bushings seem tight. I can't tell if the bushings are worn or not - I was wondering if that was a possibility.

If it matters, I have never changed the shock absorbers - do they make any kind of noise when they're 15 years old?

Anyway, I thought maybe somebody in our collective brain trust had experienced this or something similar before. I appreciate any help any body cares to throw out there as to the cause of the noises.

Good luck and take care.

 

[goldenwings]

I would guess your sway bar links are shot (clunks) and perhaps the bushings around the sway bars are also dry rotted (groans). Just my .02 Edit, the clunks may also be lower ball joints or tie rod ends but they usually only occur over bumpy sections.

 

[Mace Canute]

Well, at least I prefaced the title with it being auto-related. I was just going to ask about "Strange Noises coming from my rear end".
That would be called flatulence...or, for us lay people, farting. It's normal...don't worry about it. When people complain, just tell them to breath deep and enjoy...cause there's more where that came from!
Anyway, I've got a 1996 Isuzu Rodeo (same as a Honda Passport of the same vintage). In the last year or so, I've been getting a "thumping" noise that sounds like its coming from the back of the vehicle.

Bascially, when I make a turn, I get a "thump". It almost always happens when at a higher speed - and I mean like when I'm turning off a main road onto a side road at, like, 20 mph and its a 90 degree turn.

I also get a lot of creaking and groaning in an off-camber situation. When I turn off of a street into a parking lot that has an incline/decline apron, I get loud groans and creaks.

It seems to me like it is probably a suspension-related item, but I can't find anything out of whack. I replaced the bump stops in the fall - one had almost dry rotted off and was barely hanging on and the other one fell off when I grabbed it.

I don't see any kind of shiny areas that indicated something sliding back and forth or rubbing or anything like that. The shackle bolts and bolts at the leaf spring bushings seem tight. I can't tell if the bushings are worn or not - I was wondering if that was a possibility.Yes, that's definitely a possibility and I have seen it happen on a truck of my own.

If it matters, I have never changed the shock absorbers - do they make any kind of noise when they're 15 years old? They might but not always. If they have any oil leaking from them, they are shot and should be replaced. The bushings in the ends are also prone to wear and I have seen them pounded out completely. The thump you hear has a very good possibility of being shock related, more so than spring bushings IMHO.

Anyway, I thought maybe somebody in our collective brain trust had experienced this or something similar before. I appreciate any help any body cares to throw out there as to the cause of the noises.

Good luck and take care.

As goldenwings says, any bushing anywhere on a truck that old could very well be the culprit. It's time to give your ride a good going over and see just what all could be repaired.

 

[rtimgray]

Is the sway bar part of the rear suspension system? On the rear suspension, all I see is the leaf springs and shocks.

Aren't tie rod ends part of the front suspension? The noise is definately from the rear of the vehicle.

Also, I can make the creaking/groaning noise happen when the vehicle is sitting still and I get out and jump up and down on the rear bumper. It's the same creak/groan as I get when in the off-camber positions, but I don't hear the "thump" that I get when turning.
The two may be related or may not be, I just don't know.

Thanks for the help.

 

[Dargo]

I don't know about your rear end...boy, that sounds odd, but the groaning and creaking is likely normal. You know, sort of like some of us guys getting older. I creak and moan a lot more than I used to. I just don't want to quit creaking and moaning really soon, if you know what I mean.

I have an old '98 Jeep Cherokee Sport (cheaper model; not Grand Cherokee) that I really like. I drive it all the time just because I like it. I have a moan/low squeak in the door hinges as soon as I open the door. Turning the steering wheel side to side gets me the same noise from somewhere inside the steering column, but it still feels smooth. Sounds like something on the roof luggage rack is loose too. I've never checked to see what it might be; figure if it gets loose enough I won't have to hear it anymore.

Anyway, with body twists, one of my friends who owns a body shop tells me that the older unibody SUV type vehicles very commonly just get a bit looser as they age and flex a bit, causing some noises. He advised that as long as nothing is making a grinding or popping noise, either don't worry about it or buy me a newer Jeep. Since I like the Jeep, I have managed to tune the old age moans out and no longer hear them once I am in it for 5 minutes or so. If you "feel" the popping in the rear, you may want someone familiar with that vehicle to check it out. If you just hear it, I've found Fluid Film great for stopping old hardened rubber noises and a lot of other creaking noises. Good luck!

 

[Mace Canute]

Is the sway bar part of the rear suspension system? On the rear suspension, all I see is the leaf springs and shocks.It may or may not be, it all depends on what the manufacturer decided to equip the vehicle with. Most trucks I've seen have (anti) sway bars only on the front end.

Aren't tie rod ends part of the front suspension? The noise is definately from the rear of the vehicle.Yes, usually only found on the front end

Also, I can make the creaking/groaning noise happen when the vehicle is sitting still and I get out and jump up and down on the rear bumper. It's the same creak/groan as I get when in the off-camber positions, but I don't hear the "thump" that I get when turning. I've heard shocks make that noise, also leaf springs since they do slide a bit against each other as they go through their motions.
The two may be related or may not be, I just don't know.

Thanks for the help.

I hope this helps some.

 

[tacosteelersman]

I second golden wings post he is spot on with his info. Now have an assistant bounce the rear, and you (with sefety glasses) get under and listen and feel for the problem area. As for the thumping check your exhaust hangers and spare tire for looseness. Then grab the rear wheel (with the vehicle on the ground) and vigerously wobbel the wheel pushing towards the other wheel then pulling back towards you and listen for excessive rear end play. GOOD LUCK, keep us updated..

 

[LD1]

Is it just ONE thump, or is it a continuous tuump, thump, thump when turning?

If it is continuious and the frequency is higher the faster you go, that implys something that rotates. Like a wheelbearing or gears.

But if it is just 1 thump, it sounds like what others have mentioned. Something in the suspension.

If that is the case, you really need to get under it with someone bouncing on it and see if you can replicate the problem.

 

[rtimgray]

Yes, it is just one thump when I turn. Also, if I make successive turns in the same direction (i.e. to sharp right hand turns), I don't hear the noise on the second turn. If I do a slalom course (I think that's what it is called) then I can get the "thump" noise on each turn.

Sounds like I might want to start with the shocks and see if that makes any difference, and check out the other odds and ends while I under there.

Thanks for the help, fellas.

 

[Car Doc]

I do this for a living and a lot of those have limited slip rear ends I would check and see if its a limited slip if so change the fluid and add the LS additive. hth