Noise from rear end

I have a 2000 Silverado Z71. Over the past year I've noticed a "whoop" noise from the rear end when I start from a dead stop. I recently had a suspension lift added to the truck and now the noise seems more pronounced. Has anyone else run across this issue?

Sounds to me like the typical slip yolk clunk and by putting in a lift, you have increased the driveline angle and that is why it seems more pronounced now.

Thanks Kenny, it's not a clunk though, it's a "whoop". Would the slip yolk create that noise as well?

I think I may know what you're talking about. Is there any way you can give a more detailed description of the sound and/or feel.

There's no feel to it all, no bump or jerk or anything like like that. It's just the whooping sound. It's almost like the sound of an owl, just not as long as an owl "who" would be. This is really hard to explain in words.

This job would be no fun without getting to listen to customers make noises and then having them repeat it. ><

Could be axle wrap. How big of a lift did you add. If it was 6" and you used like a 5 1/2inch block with the factory two inch block, that is normally enough leverage to twist the axle and thats the sound you hear. Best way to tell is to leave it in park, have a buddy grab the tire and try to spin it. You get down behind the pickup and see if the axle slips around the block. The only fixes are to get traction bars. All new leaf springs, or shorter blocks and use an add-a-leaf

Thanks Bigbad but the noise was happening before I lifted the truck as well so I don't think it's axle wrap.

I was just thinking about my Silvy and I had a "hoo" kind of sound in my rear end and never thought much of it, and it didnt do it all the time. But since I re-geared and ditched the factory locker for a Auburn limited slip, I havent heard anything. But who knows

Well, I did some searching in the posts here and found a possible solution my problem. I've read that I can stick a racquetball in the yoke and that will fix it. Thanks to all for their input.

Well, I did some searching in the posts here and found a possible solution my problem. I've read that I can stick a racquetball in the yoke and that will fix it. Thanks to all for their input.


Here is a sight that may help you figure out the noise.
http://www.differentials.com/install.html


Good Luck
MT