89 Rear Wheel Clicking on Accleration, help!

[CulverC4]

Hey everyone,
I'm new here and have culled much appreciated and well used information about my C4, thanks to all.
My issue is this, when I start my car and the idle speed is up at 800-1,000 RPM, after I throw the car into reverse (auto tranny) I hear a snap-like click come from my rear end. If the car is warmed up and is idling at the normal 6-700 rpm this won't happen, but if I stab the gas pedal a bit after first placing it in reverse I can "make" the rear end click. This also occurs after I put it in drive, but again, only if the car is cold and revving higher, or if warm and I give the gas pedal a quick jab. It's important to note that once the car is rolling I won't get this again, even if I come to a stop and accelerate quickly again, no click. But once I go from drive to reverse, or vice versa, this issue will come back and click the rear, but only at initial gear change and acceleration. I had a friend stand outside of the car and walk alongside as I made the click reappear, he claimed the noise was coming from the rear passenger side wheel. One corvette mechanic (Coast Corvette, Anaheim, CA) said it sounded like a rear spindle in need of lubrication. Any ideas?

 

[Ugolino]

In my experience, there's only a couple of things that can click back there, either the splines or one of the half-shaft u-joints.

 

[CulverC4]

Sorry, I meant the splines, not the spindle! I had the U joints replaced, front and rear, about 6 months ago, but I think that was for the transmission, not the half shafts. I'll have the half shafts' U joints checked out. If it is the splines, what might be the fix? Or do I need to replace it?
Thanks in advance!
Jose

 

[Robertwav1]

Once I had an issue with my 93 drivers side rear wheel clicking like you talk about, very annoying. The car was under warranty at the time and they replaed the half shaft joint but that didn't do the job, took it back and they said something about what I can remember about a spacer in the rear wheel needed to be replaced. I guess a breakdown of the mechanics on the rear wheel might give you some clues. Hope it helps!

 

[jrzvette]

Do a search on this and the other forums (CF, DC and C4Guru). This is a common complaint among C4 owners and it's usually attributable to a missing or defective teflon washer in the rear half shafts. Aside from being annoying it's usually nothing to worry about.

 

[geekinavette]

This is an issue that showed up as a TSB later in the C4 models...the "clicky" (or "klinky" as I called it) is coming from the axle shaft shifting positions within the bearing splines, when you change directions (going from D to R and vice-versa). My 84 did it BAD, and it annoyed the HELL out of me. The "fix" calls for lubrication the splines with anti-sieze grease, and installing a washer between the end of the axle shaft and the bearing so that the axle shaft pulls tighter up against the bearing.

This diagram shows the location and part number for the washer (I added the stuff in blue to make it easier to see, and also added a NAPA part number for the dust seal in the back side of the spindle assembly that GM no longer carries...NAPA did a kick butt job of finding that seal!).

Good luck!

Bill

 

[pgtr]

Interesting...

When was this TSB done? And did they modify later production C4s?

When driving/riding in a couple late C4s (95?) I've heard something that sounded like this esp when the window(s) was down.

Interesting thread - thanks!

 

[G Winter]

I am not real sure but I think my 90 does this real faintly. I assumed it was a joint. Nice to be informed on this so I can address it this summer. Is it only the left side that has the problem?

Glenn

 

[gmjunkie]

I am not real sure but I think my 90 does this real faintly. I assumed it was a joint. Nice to be informed on this so I can address it this summer. Is it only the left side that has the problem?

Glenn

No Glenn,either will do it!! The left side is just usually the one that is heard first!!

 

[Robertwav1]

This is an issue that showed up as a TSB later in the C4 models...the "clicky" (or "klinky" as I called it) is coming from the axle shaft shifting positions within the bearing splines, when you change directions (going from D to R and vice-versa). My 84 did it BAD, and it annoyed the HELL out of me. The "fix" calls for lubrication the splines with anti-sieze grease, and installing a washer between the end of the axle shaft and the bearing so that the axle shaft pulls tighter up against the bearing.

This diagram shows the location and part number for the washer (I added the stuff in blue to make it easier to see, and also added a NAPA part number for the dust seal in the back side of the spindle assembly that GM no longer carries...NAPA did a kick butt job of finding that seal!).

Good luck!

Bill

Nice job on the print!

 

[CulverC4]

Wow! Thanks geekinavette, your diagram (especially the Napa and GM part numbers) is not only extremely helpful, but I'd argue above and beyond duty! Now I can walk into the shop informed, and hopefully drive out with the issue resolved later that day!

 

[geekinavette]

Quite welcome...good luck with the repair!

Bill