Left rear clunk

[MuRCieLaGo]

Hi,

When I bought the car, there was a clunk on the rear left suspension. I've been to 3 different garages and none of them could tell me where's the problem (including official inspection).

Can't see anything wrong from underneath.

You guys got any idea?

[secondchance]

Can you describe the noise with more detail?

[BigIke]

I just had an inner half shaft u-joint fail, was doing the same thing.

When your driving, will it pull to one side when you load it, then pull to the other when you unload? I think torque steer is a good indicator of a failing u-joint.

Roll down driver and passenger windows, jack up the drivers side. Block the wheels, off the parking brake, put the car in neutral. Now grab the driver (left) half shaft and rotate it back and forth.

Got sloop? Replace the u-joints with.

2 x http://www.amazon.com/Spicer-5-3615X-Special-Non-Greasable-Universal/dp/B00DOH3JFY?ie=UTF8&psc=1&redirect=true&ref_=oh_aui_detailpage_o02_s02
2 x http://www.amazon.com/Spicer-3-70-48X-Bearing-Strap-Kit/dp/B00GAPECGC?ie=UTF8&psc=1&redirect=true&ref_=oh_aui_detailpage_o02_s01

Safety First :)
https://scontent-dfw1-1.xx.fbcdn.net/hphotos-xat1/v/t1.0-0/p280x280/13001284_1317440704935922_629845609943195604_n.jpg ?oh=ba0f910c05cb2bf2389a64c35b9935b8&oe=57B5B3D4

[Jagdpanzer]

Another good u-joint source
http://www.dennysdriveshaft.com/p422_1984_to_1996_corvette_aluminum_rear_axle_half _shaft_rebuild_.html

[MuRCieLaGo]

Will check that out, thanks guys!

[MuRCieLaGo]

Everything seems to be tight there, I recorded a quick video of the clunk.

https://www.youtube.com/watch?v=QYQbYYCz-Ag

[5ABI VT]

my guess is the sway bar end links. Have they been changed before or do they look in good condition? the rubber deteriorates over time and the metal sleeve will clink/clunk on the sway bar going over bumps.

[WARP TEN]

my guess is the sway bar end links. Have they been changed before or do they look in good condition? the rubber deteriorates over time and the metal sleeve will clink/clunk on the sway bar going over bumps.

I agree. I had a clunk in the rear of the 95 when I backed out of my driveway. Only 21,000 miles on the car. Marc looked it over and didn't see anything obvious but said the sway bar bushings looked dry. Replaced them and the clunk was gone. --Bob

[MuRCieLaGo]

Would make a bit of sense. I will remove the sway bar link, and see if the clunk goes away (I know a car can drive fine without a sway bar). I'll change it if I don't hear the clunks anymore.

[RussMcB]

I changed my links recently and my original, old bushings were in very sad shape.Would make a bit of sense. I will remove the sway bar link, and see if the clunk goes away (I know a car can drive fine without a sway bar). I'll change it if I don't hear the clunks anymore.FYI, (in case this saves you 10 min) - You can probably just remove one of the end link bolts, then tie-wrap the end link snugly temporarily as a test (rather than remove the entire end links).

[MuRCieLaGo]

I changed my links recently and my original, old bushings were in very sad shape.FYI, (in case this saves you 10 min) - You can probably just remove one of the end link bolts, then tie-wrap the end link snugly temporarily as a test (rather than remove the entire end links).

That's a good idea, thank you!

[MuRCieLaGo]

Here's another sound, not sure it is related to the clunk. I only hear it when I leave a stop sign.

https://www.youtube.com/watch?v=NWRoRBPQT1A

I'm now officially upset by the quality of the ZR-1. Got a new problem showing up week after week after week.

[Billy Mild]

What are you torquing the axleshaft nut too?

I did 175 ft/lbs and for a few days the click noise was gone, now its bad. I replaced the washers too and used antiseize on the shaft splines.

[5ABI VT]

Here's another sound, not sure it is related to the clunk. I only hear it when I leave a stop sign.

https://www.youtube.com/watch?v=NWRoRBPQT1A

I'm now officially upset by the quality of the ZR-1. Got a new problem showing up week after week after week.

Its hard to tell in the video which noise it is that you are referring to. Can you describe it in any more detail ? Is it happening when the wheels are moving slowly and goes away at speed? If the fear pads are worn and given their age.. With a little air in the fluid or a dirty piston bore etc it's possible the pads aren't seated flat against the rotor or a previous owner may have put the pads in with the anti rattle springs on the outside of the caliper ? Just shooting off ideas that cross my mind.

Sucks to hear your frustration I feel that way a lot of times .

[5ABI VT]

Someone else mentioned this to me on Instagram but they had a rattling and clunking noise may low speeds and it was the hatch struts. They were worn and they were rattling over bumps. Did you check the end links or replace them ?

[MuRCieLaGo]

Billy Mild, I haven't touched the axle nut since I got the car. If it is not too much of a pain, I'll try to torque it.

5ABI VT, pads are a good idea. Sometimes when I break, I'm hearing that typical worn brake pads sound.

The noise is there only at low speed, until about 10 mph, when I accelerate.

For the initial clunking noise, I'll open my hatch tomorrow and see if the clunk goes away.

I did not check the end links yet...

Thanks for your support guys!

[5ABI VT]

Can try pulling the ebrake slightly when accelerating from a stop see if the noise stops. Also don't forget to check the torque on the wheel bolts.

[BigJohn]

Sway bar bushings?

[MuRCieLaGo]

Can try pulling the ebrake slightly when accelerating from a stop see if the noise stops. Also don't forget to check the torque on the wheel bolts.

Just tried it a few minutes ago, noise is still there.

Sway bar bushings?

For the clunking sound, maybe (but I doubt it). 3 local garages checked everything underneath and it was all fine, including "official state inspection".

[RussMcB]

Is the clunking a steady frequency, such as every wheel or driveshaft revolution? In other words, do you hear the clunks twice as fast when you're going 10MPH compared to 5 MPH?

If yes, the problem is in the drivetrain (transmission, driveshaft, differential, halfshaft, hub/wheel/brakes).

Do you have a small video camera (i.e., GoPro)? Perhaps you can mount it close to different components (close enough to help hear the clunk source). I think the audio might be more useful than the video.

I have a cheap mechanic's stethoscope. Perhaps you could use one, or have a passenger use a big long screwdriver in a similar fashion, hold it against the shifter the see if the clunk is coming from the trans. Maybe since it's only at low speeds it's related to first gear? (wild guess).

I like the e-brake suggestion earlier. That's a good way to see if it's related to rear pads, rotor.

Can you put on different rear tires/wheels for a test drive to see if the clunk goes away?

Can you put a buddy in the back with the hatch open to see if it's coming from one side (or from the front or back)?

Changed trans and diff fluids recently? Anything other than clean oil come out?

Can you hear a clunk when the rear wheels are turning with the car up on jack stands?

Good luck.

[XfireZ51]

If it has not been mentioned, one other thing to check is the torque on the half shaft to hub nut. It may come loose and only held in by cotter pin.

[mike100]

If it has not been mentioned, one other thing to check is the torque on the half shaft to hub nut. It may come loose and only held in by cotter pin.

and I will also add to put some grease on the axle splines. it gets lightly rusted and dry and if it can't slide smoothly- it can make a 'pop' noise every time you add or remove torque.

[secondchance]

Murcielago,

It helps if you can describe the type of noise and when it makes the noise.

If you are hearing one "clink" moving forward from stop in 1st gear, stop the car, go into reverse and back up. If you hear same "clink" (or clank) one time, it is your rear hub bearing. I believe factory manual originally called for 160 or 170 ft-lbs. This was revised later by Chevrolet to 190 ft-lbs. If this is your noise source, you might get lucky and noise might go away after re-torquing the axle nut.

If you are hearing clanking noise while driving and going over bumps where car is swaying left/right, I would suspect sway arm bushing (lower and/or upper- two on each side).

Good luck!

[MuRCieLaGo]

Is the clunking a steady frequency, such as every wheel or driveshaft revolution? In other words, do you hear the clunks twice as fast when you're going 10MPH compared to 5 MPH?

If yes, the problem is in the drivetrain (transmission, driveshaft, differential, halfshaft, hub/wheel/brakes).

Do you have a small video camera (i.e., GoPro)? Perhaps you can mount it close to different components (close enough to help hear the clunk source). I think the audio might be more useful than the video.

I have a cheap mechanic's stethoscope. Perhaps you could use one, or have a passenger use a big long screwdriver in a similar fashion, hold it against the shifter the see if the clunk is coming from the trans. Maybe since it's only at low speeds it's related to first gear? (wild guess).

I like the e-brake suggestion earlier. That's a good way to see if it's related to rear pads, rotor.

Can you put on different rear tires/wheels for a test drive to see if the clunk goes away?

Can you put a buddy in the back with the hatch open to see if it's coming from one side (or from the front or back)?

Changed trans and diff fluids recently? Anything other than clean oil come out?

Can you hear a clunk when the rear wheels are turning with the car up on jack stands?

Good luck.

It's coming from rear driver side only. I can't hear anything for sure when the car is up on jack stands. Thanks for all the ideas!


Murcielago,

It helps if you can describe the type of noise and when it makes the noise.

If you are hearing one "clink" moving forward from stop in 1st gear, stop the car, go into reverse and back up. If you hear same "clink" (or clank) one time, it is your rear hub bearing. I believe factory manual originally called for 160 or 170 ft-lbs. This was revised later by Chevrolet to 190 ft-lbs. If this is your noise source, you might get lucky and noise might go away after re-torquing the axle nut.

If you are hearing clanking noise while driving and going over bumps where car is swaying left/right, I would suspect sway arm bushing (lower and/or upper- two on each side).

Good luck!

secondchance, once again you won. I just tightened the axle nut (barely tightened it) and the 2nd noise (low speed) went away.

Gotta work on the clunk now. Like somebody said earlier, I will remove a link end to see if the noise goes away. It should help pinpointing the problem.

Thanks all!

[MuRCieLaGo]

Oh well, it was only fixed temporarily. Same noise came back. Gonna try to tighten the axle nut to exactly 190 ft-lbs.

EDIT: It was too tight, I tighten the nut to exactly 190 ft-lbs and the noise went away... For how long?