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-   -   Lound Clunk on Clutch Release (http://www.wranglerforum.com/f210/lound-clunk-on-clutch-release-59735.html)

tjmaddieva 08-27-2010 12:34 PM

Lound Clunk on Clutch Release
 
I recently replaced the entire exhaust system and afterwards discovered a lovely (NOT!) clunking noise ever time I release the clutch -- whether driving or just sitting. I have looked at other forums and got advice to replace the u-joints at the rear drive shaft, which solved another person's similar problem, however, it didn't solve mine. Any ideas??

Gate53 08-27-2010 12:38 PM

Is the exhaust pipe hitting the tub when you take off? Does it do it in reverse?

tjmaddieva 08-27-2010 12:40 PM

I'm pretty sure it's not hitting it. It doesn't do it in reverse.

DontTellMeAboutCajun 08-27-2010 01:04 PM

My '97 clunks too, it's the muffler hitting the transfer case skid plate because of a loose exhaust manifold/exhaust pipe connection. Ensure your exhaust pipe is secure, when the engine bucks it may be hitting somewhere.

tjmaddieva 08-27-2010 01:10 PM

I'm pretty sure it's coming from farther back than that, but I'll check on that too. Thanks!

Gate53 08-27-2010 01:11 PM

Not doing it in reverse might tell you it's the exhuast since that's what you changed and it started.

Gate53 08-27-2010 01:11 PM

it does go all the way back:)

tjmaddieva 08-27-2010 01:13 PM

lol. Thanks.

Gate53 08-27-2010 01:13 PM

Put on some gloves and try to wiggle it to see if it hits anything.

tjmaddieva 08-27-2010 02:42 PM

Well, I went under and tried to find something lose that could be the cause of the awful clunk, but it's all secure...any other ideas?

Thesnufalufagus 08-27-2010 02:50 PM

My exhaust tip hits my tow hitch when I give it a good bit of gas on takeoff

tjmaddieva 08-27-2010 02:52 PM

I don't have a tow hitch, so I know it can't be that. lol :)

NickM 08-27-2010 04:27 PM

I would look real closely at your control arm bushings in back-both upper and lower.
Does it shift side to side under acceleration/deceleration?

Nick

chrisb0108 08-27-2010 04:38 PM

Most of the things mentioned would require her to be moving....her original post said it happens when she releases the clutch driving AND sitting still.

tjmaddieva, you said you discovered the noise after the exhaust job.....how soon after the exhaust job did you start hearing it? Maybe the exhasut isn't associated with the noise. Have you had someone sit in your Jeep and push the clutch while you get under it so that you can possibly isolate where the noise is coming from? I'd do that if you haven't already. May get some more accurate suggestions here if you can tell a little better where the noise is coming from.

NickM 08-27-2010 04:56 PM

Quote:

Originally Posted by chrisb0108 (Post 745438)
Most of the things mentioned would require her to be moving....her original post said it happens when she releases the clutch driving AND sitting still.

tjmaddieva, you said you discovered the noise after the exhaust job.....how soon after the exhaust job did you start hearing it? Maybe the exhasut isn't associated with the noise. Have you had someone sit in your Jeep and push the clutch while you get under it so that you can possibly isolate where the noise is coming from? I'd do that if you haven't already. May get some more accurate suggestions here if you can tell a little better where the noise is coming from.


Actually, mine did the same thing as soon as you would release the clutch, even without any actuall movement-the axle was winding that easily.
It would not have, however, done that letting the clutch out in neutral.
The exhaust is also supposed to have a hanger at the trans as well, it would be easy to miss if it was not put back into that mount correctly.
I definatle agree with having someone sit in the seat and push the clutch repeatedly while she checks the underside thoroughly though.

Nick

tjmaddieva 08-27-2010 04:59 PM

I mentioned the exhaust because the leak was loud and prevented me from hearing it. Once it was no longer loud, I discovered the quieter noise. I guess I wasn't very clear.

tjmaddieva 08-27-2010 05:02 PM

Okay, just had someone pusing on the clutch for me. The lower control arm is sliding back and forth. Does that mean it needs new bushings or that it just needs to be tightened?

awcressey 08-27-2010 05:14 PM

Mine did the same thing and it turned out that it was in catalact (pardon the spelling) converter hitting the skid plate. If it isn't as tight as possible then it will rattle

NickM 08-27-2010 05:43 PM

When the lower arm moves, do you see the bolt moving as well? If so, the holes have self reamed....might be able to stabilize by retorquing to 130'#.
If they move a bunch, the bushings are probably shot and need to be replaced. Do all four bushings and take a good look at the uppers as well.
Mine are very temporary, had to steal sleeves from an old pair of factory arms as the Pro Comp ones had folded and would just wrinkle as you put the torque to them.
Ultimate cure will be new arms with JJ's, but that might not be in the OP's budget.
OP, look at the inside of the mounts-have the bushings worn the paint off sliding around?
How about the outside of the brackets-if the bolts are moving, you will see wear from that.
If the bolts are not moving, that is probably your best scenario, as you can just drop the arms and replace the bushings-good as new.

Nick

chrisb0108 08-27-2010 07:13 PM

I don't understand how the control arm can move just by pushing the clutch even when the Jeep is sitting still.

Edit: Sorry, just saw Nick's response about the axle winding. Can you explain though what you mean by that? Why would the axle have that much movement in it from pushing the clutch even when the Jeep is sitting still? Sorry for all the questions, can't learn too much though....right

jdmtru 08-27-2010 08:20 PM

Tjmaddieva Where at in Falls church u live I live near Harrisonburg...

rrich 08-27-2010 11:45 PM

You grabbed and shook the exhaust and it wasn't loose.

But if the engine mounts or trans mount were loose, the engine and trans could be rocking when you release the clutch. You'd never notice it by shaking the exhaust.

Open the hood, watch the engine while someone operates the clutch. The engine shouldn't move appreciably.
More than likely it's the left engine mount since that's the one under tension when torquing the motor.

Obviously the new exhaust is a little closer somewhere than it was before.

NickM 08-28-2010 03:50 PM

Quote:

Originally Posted by chrisb0108 (Post 745612)
I don't understand how the control arm can move just by pushing the clutch even when the Jeep is sitting still.

Edit: Sorry, just saw Nick's response about the axle winding. Can you explain though what you mean by that? Why would the axle have that much movement in it from pushing the clutch even when the Jeep is sitting still? Sorry for all the questions, can't learn too much though....right

If she is letting the clutch out, even if the rig has not moved yet, the axle can still shift around from the applied torque.
The OP never said anything about being in neutral, and what she discovered bore out my theory on what was going on.
If it is winding up on application of torque, when you push in the clutch you are removing torque and it is relaxing the other direction.
What she observed leads me to believe that the bushings are shot but the mounts are still fine.
Hopefully the OP will have a chance soon to tear into it and let us know what she finds.
OP, are the arms stock or aftermarket?
If stock, those rubber bushings can get real nasty soft over time and definitely lead to the symptoms.
Factory arms can get away with poly bushings and not bind, since the arms themselves can twist about their axis so readily.

Nick

tjmaddieva 08-28-2010 04:35 PM

The control arms were stock. I replaced them today and it seems to have taken care of the problem! Thanks so much everyone!!!

NickM 08-28-2010 09:08 PM

Very good.
Probalby cured some handling ills that you had not noticed but will be apparent by their absence now (ie:rear end squirming around, maybe some torque steer on the shifts).

Nick

Gate53 08-28-2010 09:12 PM

Glad you found it Maddie, good job! And good call Nick.


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