Rear "clicking" sound

[Duke W.]

Re: Rear "clicking" sound

Duke,

Thanks for the input. Every bushing is new. I did a complete rear suspension rebuild (using "stock" replacement parts, no fancy urethane bushings) two summers ago. Had the car over at a friends shop in June and we went over the front differential bushing and bolts (as you suggest). All are in good shape and properly torqued.

Tomorrow I plan on tearing into it. Hopefully I'll have some answers tomorrow evening........

Thanks,

Tom

Since your description indicates the noise may be torque sensitive the front diff. mount is suspect, so I would check it again including the bracket to carrier fasteners. It could even be something as simple as loose wheel nuts.

Clicking sounds at startup and as you come to a stop can also indicate wheel bearings, and they are easy to check.

If a bearing is spalling the clearance will loosen up noticeably, which you can tell by doing the "wiggle test" with the wheels off the ground. Grabe the top and bottom of the tire from the side and wiggle it. All four should have about the same amount of perceptable play.

The U-joints can be similarly checked by looking for any play. There should be none.

Duke

[Joe L.]

Re: Rear "clicking" sound

[quote=Duke Williams (22045);366019]Since your description indicates the noise may be torque sensitive the front diff. mount is suspect, so I would check it again including the bracket to carrier fasteners. It could even be something as simple as loose wheel nuts.

Clicking sounds at startup and as you come to a stop can also indicate wheel bearings, and they are easy to check.

If a bearing is spalling the clearance will loosen up noticeably, which you can tell by doing the "wiggle test" with the wheels off the ground. Grabe the top and bottom of the tire from the side and wiggle it. All four should have about the same amount of perceptable play.

The U-joints can be similarly checked by looking for any play. There should be none.

Duke[quote]


Duke and Tom-----


U-joints can appear to be ok from the perspective of no perceived "play", but that does not necessarily mean they are ok. I've seen these joints, especially the half shaft joints, be completely "wiggle free". However, when the bearing caps were removed, the trunnions and needle bearings were TOTALLY wiped out. If there is even SLIGHT brinneling of the trunnions, this can cause "clicking". To assess this one has to remove the caps, clean the trunnions thoroughly and inspect them with a magnifying glass. If even the slightest brinneling is observed on ANY trunnion, the u-joint is scrap. You'd be absolutely amazed how fast this can happen to joints even with low mileage on them.

Also, the needle bearings need to be inspected. If any show any evidence of corrosion or damage, they need to be replaced assuming the trunnions are perfect (unlikely if the needle bearings are not perfect). "Black spots" on the needle bearings are corrosion or extreme pressure damage.

[Duke W.]

Re: Rear "clicking" sound

At about 70K miles my car developed a "knock" with torque reversal. Upon inpsection on a lift and rotating the the wheel back and forth I could clearly see play in one of the tunnions/cups.

If you have to go so far as to remove the halfshafts to inspect the joints, I would just replace all of them. The outboards seems to go first - probably because they are more subject to road splash, and a little bit of water/dirt will corrode/wear them away is short order.

Duke

[Thomas H.]

Re: Rear "clicking" sound

Ok, I spent the better part of today going over the right rear to find the source this elusive noise.

Here is what I did:
First I checked all hardware that I could get a wrench. I found nothing loose.

I wiggled, yanked and pushed one the tire as well as the various components and there is nothing loose. (remember all of the suspension was rebuilt less the 300 miles ago)

I then removed the half shaft. I could not see anything wrong or unusual with the u-joints. I did not remove the u-joints from the shaft, but did remove the end caps I could and they appeared well lubricated and not missing any needle bearings. (Thanks for the suggestion Joe, although I did not go to the level of inspecting the actual bearings individually)

I checked the rear bearing play, measured play of .002", well within spec. Also the rotor spins smoothly without and play or binding.

I noted that the brake pads seemed to have a lot of play fore/aft. I added some clip on .025" shims to the end of the pads to take up some of the slack.

So.... after not finding anything unusual I put it all back together and went for a test drive. Guess what? Yup, the noise is still there.

It only occurs on acceleration from a stop, and goes away once I get going. I can sometimes hear is when letting off the gas abruptly.

After reading Joe L, Joe C and Dukes last posts, I think I'm going to go ahead and replace the u-joints. I'm starting to think that eventhough these are new, it would be best to replace them. Any suggestions on a particular brand? The ones I used were Spicers with grease fittings.

I am also officially changing my description from a "click" sound to a "snap" sound. I went to a industrial building with a parking lot along it and drove back and forth listening. It is definitly coming from the right rear.

I took my daughter (she'll be 16 tomorrow.............. ) along and had her use her phone to take a video of the car. The videos are attached. The first being a better example of the noise. Keep in mind these are not the best videos, but a fair example of the noise.

http://s21.photobucket.com/albums/b298/tmh454/?action=view&current=Video0013.flv

http://s21.photobucket.com/albums/b298/tmh454/?action=view&current=Video0014.flv

As usual, thank you to all for the support!

Regards,
Tom

[Harmon C.]

Re: Rear "clicking" sound

That sound is more like E-brake parts rolling around in the drum than U joints. It sounds somewhat like stones in a hubcap. Is this a four speed?

[Thomas H.]

Re: Rear "clicking" sound

Lyle,

One of the things I did when the half shaft was off was to adjust the e-brake. I set it to the point where I could not turn the rotor, then backed it off to where I could turn the rotor. Also had someone work the lever while spinning the rotor. It seemed to function just fine, with no noises.

I'm trying to avoid drilling out the rotor rivets since Bairs did such a nice job of putting them in and I won't be able to re-install them.

I think if the u-joints don't fix it, I'll remove the trailing arm assembly and send it back to Bairs for evaluation. Luckily we are both in PA so shipping won't be too expensive..........

Thanks for the input,

Tom

[Thomas H.]

UPDATE Re: Rear "clicking" sound

Finally got the car back together this weekend after sending the trailing arm back to Bairs. They could find no problems with it. I had them re-assemble it with new parts and send it back to me. (Ed at Bairs was very helpful, as always......).

So, I put the newly rebuilt trailing arm back in the car along with a new strut rod (since the bushing was deformed on the old one, see my other posts on the bushing) and a new halfshaft. Bled the brakes, fired it up and went for a ride. Guess what......... NO noise! Finally.

What was the ultimate issue? I can't say for sure since I found obvious bad parts, but at least the only thing I hear now is the sweet rumble of the LS5 under the hood.

A quick wash and a coat of polish and off to the local monthly car show with a noiseless rear (the car's rear that is............)

As usual, thanks everyone for the helpful hints

Tom

[Robert R.]

Re: UPDATE Re: Rear "clicking" sound

Tom,
While you were posting the symptoms, a similar noise was coming from the right side on my '73. Turns out that after 35+ years, a spring, part of the emergency brake setup, snapped and was dragging inside the rotor. Could that have been the culprit in your noise issue, even though they said things were fine?

Bob

[Stephen B.]

Re: Rear "clicking" sound

I've had clicking noises from the parking brake mechanism.

[Thomas H.]

Re: UPDATE Re: Rear "clicking" sound

Bob,

It may have been, although I saw no evidence of spring issues when I took the rotor off. Either way, it seems to be fixed now............

Tom

[Thomas H.]

Re: Rear "clicking" sound

Stephen,

Parking brake issues seem to be a common thought. When I was drilling the rotor rivets off, I was fully expecting to find something, but never did. I wish I could say that is what it was, bottom line is that I can't say just what it was.

Tom

[Joe C.]

Re: Rear "clicking" sound

Stephen,

Parking brake issues seem to be a common thought. When I was drilling the rotor rivets off, I was fully expecting to find something, but never did. I wish I could say that is what it was, bottom line is that I can't say just what it was.

Tom

Tom,

I'm glad that you had the guts to drill out the rivets and separate the rotor from the hub. There is too much mis-information here about that not being the proper thing to do.
Some purists, albeit those who have little or no practical knowledge still insist that doing so will cause hellfire and brimstone to rain down upon you!!! So doing will cause the divorced rotor/hub assembly to cause vibrations so violent, so catastrophic, as to separate you from all of your dental fillings.

Joe