Problem or coincidence?

[hockey_19pro]

Just want to start out saying that I love this thread, it's been really helpful for me since I'm completely dumb when it comes to vehicles. With that said, I have a 2000 GMC Sierra Z71 with 13900 miles. I just bought it early this fall and never noticed anything wrong when it was warm out, but since it's been so cold out I've noticed a "clunk" sound when shifting from PARK to REV. Once it's warmed up though, there's no "clunk". Could it be the the U-joints or...?

[Macgyver55]

Could very well be u-joints. When cold, idle speed is higher and transmission pressures are higher, making it more likely to clunk when cold. After it warms up, idle slows and pressure relaxes some so it shifts a bit smoother. Its a good idea to have it looked at.

[hockey_19pro]

I was afraid someone would say that...I'm kind of crunched for money (in college) just like everyone else. Any idea of a price range for this?

[Tyler23]

i got the same issue with my pickup.. im pretty sure its the rear end that has some slop cuz when i grab the drive shaft in neutral i can move it back and forth some... maybe this is like yours?.. a mechanic i know said its prolly just wore and ill have to shim it over.. ill tackle that one the ice is gone goodluck!

[muddpuppy]

I have a 03 Z71 I had the same issue it would also happen inbetween gears at slow speeds. The fix was to pack a part of the drive shaft yoke area with Grease. I was told after waranty was up to put a grese zyrk in that spot to remedy the issue in the future. I have not had the issue since they repaired it.