Jump to content
HybridZ

CV JOINT CLUNK?


HICKL

Recommended Posts

Trying to track down a clunk...will a cv that is low on grease clunk?

 

I am running a welded dif and understand that this is brutal on cv's when turning. My passenger side seems to make a bunch of noise when turning while the left does not. I found my inner boot to be torn to shreds so I swapped out that cv with another. I drove it about 20 miles and started noticing the same clunks. When I got home, I found that this inner boot was damaged also and had slung out some grease.

 

Could this be causing my clunks or just a mess of grease on my a-frame....

 

Thanks

Jeff

Link to comment
Share on other sites

  • 2 weeks later...

You can disassemble the CV and see if the balls are really loose in the joint. If there is a lot of slop, that could cause the noise. Whenever someone says rear end clunk with a Z I'm tempted to say that it's probably a diff mount issue, since that is a known problem with these cars. Search "clunk" here and at www.classiczcars.com and you'll find pages and pages of results. The boot must be coming in contact with something under the car. They normally don't go bad because they aren't doing a lot of turning like a CV in a FWD car. I wonder if a bad diff mount is allowing the diff to move and it's hitting something and tearing up the boot...

Link to comment
Share on other sites

You can disassemble the CV and see if the balls are really loose in the joint. If there is a lot of slop, that could cause the noise. Whenever someone says rear end clunk with a Z I'm tempted to say that it's probably a diff mount issue, since that is a known problem with these cars. Search "clunk" here and at www.classiczcars.com and you'll find pages and pages of results. The boot must be coming in contact with something under the car. They normally don't go bad because they aren't doing a lot of turning like a CV in a FWD car. I wonder if a bad diff mount is allowing the diff to move and it's hitting something and tearing up the boot...

 

I have recently switched to the RT mount and when I did, it changed the angle of the diff so that when I load the suspension, the rear of the diff squats and the cv rubbed the lower a arm (thats what killed the first boot). The second boot had a knick in it from laying around the shop. I shimmed my upper mustache bar bushings to tighten them up in hopes of limiting the "dip" under load and it seemed to help. I am considering going with the arizona Z car rear mount as a more permanant fix.

 

Other than that, all seems tight under there.

 

These are OEM CV's.

Link to comment
Share on other sites

Are you running poly bushings? Sounds like rubber if you're getting a lot of movement from the bushings. Poly would be a cheap and easy fix.

 

They are rubber. I thought about that, but did not know how much of my flex was in the rubber or the bar itself. Is there a disadvantage to the billet bar other than the cost?

Link to comment
Share on other sites

Not really any disadvantage if you're pretty rigidly mounted in front. If you're using a stock front mount, I think aluminum is a bad choice for the mustache bar because it isn't springy and won't allow for the front end coming up, but if you have the RT mount that pretty well fixes the front of the diff, so the aluminum bar doesn't have to deal with a lot of twist.

Link to comment
Share on other sites

Forgot to say that I would suspect with the amount of power that you have, you are probably pulling the M bar down so that it hits the washers on the bottom. Those washers have a rubber bumper on them, but I would still guess that this is the source of your clunk. If you replace the bushings with with poly there will be much less movement there. The AZC bar uses poly too, so either way will get the job done. Post when you figure it out, I'll be interested to see if I'm right.

Link to comment
Share on other sites

Forgot to say that I would suspect with the amount of power that you have, you are probably pulling the M bar down so that it hits the washers on the bottom. Those washers have a rubber bumper on them, but I would still guess that this is the source of your clunk. If you replace the bushings with with poly there will be much less movement there. The AZC bar uses poly too, so either way will get the job done. Post when you figure it out, I'll be interested to see if I'm right.

 

 

My "rubber bumps" were chewed up so I made aluminum spacers and stuck in there to remove any slack as a temp troublshooting fix. The clunks or clanks I hear are at low speeds like turning in a parking lot. Keep in mind from the first post that I am running solid dif so I know that it is forcing things to bind unaturally. I expected some of this, just seems more extreme than I anticipated and all seems to come from the same side (passenger)

Link to comment
Share on other sites

Do you have the spacers top and bottom? If so, and they're nice and tight, then I don't think the M bar is the source of your problem. Sounds like your clunk is now a clank. What are you running for the stub axles? MM adapter on a stock axle? Any play in the splines there? All bolts tight?

Link to comment
Share on other sites

just did the spacer on the bottom, I don't think that is the source of the sound either. Running stock stub axles, made my own adapters, I think there are still pics in my photo album (am kind of proud of them, stole the best of a few designs and put together). I did not feel any play when I swapped the cv and I pulled my adapter out and put back in so I know it is tight and was tight.

 

Am curious to hear from someone else running a solid dif and CV's to see if they have any of the same issues...

Link to comment
Share on other sites

If you just have the spacer on the bottom the diff you should put some on the top too or just switch to poly and see if that changes things at all.

 

My goal was to get keep the dif pushed up as far as possible to help my cv rubbing issue so I took up all the slack from the bottom. I do see what your saying though. I will just have to start over and re-look at everything as it seems that I have covered it all but still have a problem.

 

thanks for the input.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...