Anyone w/ simillar experience?

[secondchance]

Sorry for posting this in multiple locations. I need as much input on this from you guys as possible.

I get this clunking noise, very simillar to bad u-joint, when the rear tire loads up initially, either forward or backwards. Noise goes away when the load is constant. A couple of days ago, local mechanic removed the nut holding stub shaft onto rear hub/bearing assembly and then retightened it. Noise went away for 2 days. And today its coming back. He suggested that I replace the bearing and the stub shaft to get rid of the noise.
Another mechanic, I use to deal with, tells me that he still suspects U-joint. By retorquing, he thinks that it just realigned the u-joint temporarilly.

 

[6 Shooter]

How many miles on your ZR-1?

 

[RalleyRed]

I'd replace the u-joints first, I'd hate to pay for bearings and a stub shaft only to find out later that the u-joints were bad.

 

[secondchance]

A little over 60,000.

 

[6 Shooter]

I imagine if that Rocket/LT5 been hitting those u-joints with some nasty hole shots, it could take em out.

 

[secondchance]

Do you think dumping the clutch at 3500 rpm might have something to do with it?:t

 

[cntrhub]

Check the U-joints for grease weeping out of the caps. This is usually a telltale sign the needle bearings lost tolerance inside the caps. The U-joints will have a pepper coating of dirt around the cap's female ends. Take a screwdriver and load the U-joints, at both angles. See if there is any movement?
A good way to tell if the U-joints are out, is to place the car in forward gear, hold the brake pedal down, and give just a slight throttle application. You don't want to squeal the tires, you just want to load the U-joint in one direction. Then next, with the brake still applied, select reverse. You should hear a clunk or snapping sound when the Trans goes in reverse. If one joint is going south, the others will soon follow. Might as well change all of them.....if this a U-joint problem, that is?

 

[secondchance]

Thats what makes it baffling. I don't see any typical signs of U-joint failure. Such as excessive play or any grease leaking out.

 

[vettl83]

Do you think dumping the clutch at 3500 rpm might have something to do with it?:t

Only if your running super sticky tires. If I launch mine at 3500 rpm w/BFG TA's the tires just keep spinning until you back off the throttle.