03 Z71 hoe w/ tranny noise, please help

[btray]

rattling noise coming from tranny while in gear and rolling jacked upped rear tires...noise is simular to a heat shield or cat converter pitch rattle...u joints and drive shaft seem solid and noise is definately forward...thanks for any help you guys can steer me toward.

Bill

 

[Weave]

You may want to pull the driveshaft and check your u jopints I just had to replace mine and it's an 03 Z71 too. Or you could put your window down and let it idle in gear. When it is rolling if you hear squeking noise then it's your u joint. Mine in the rear was bad. Hope this will help you out!!!!

 

[btray]

I'de be really surprised but I've been fooled before...best to follow your gut feeling.

Thanks for the reply

 

[chrias]

Check your O2 sensors. Sometimes the caps on them loosen and cause a rattle. If you're hearing a rattling only when the truck is moving then it's a u-joint issue. If it's 4wd also check the u-joints on the front driveshaft.

 

[btray]

Thanks for your reply...going to check those oyx sensors...that was just all replaced and we have a code being thrown on oyx sensor left bank...pulling the drive shaft tonight and running the tranny without hooked up to see if noise persist.

thanks again

Bill

 

[btray]

for anyone interested, it looks like it's the chain drive in the transfer case...pulling down shortly...mechanic said sounds like what I was discribing...anybody know about this problem or is this abnormal...only75,000 miles on z71 Tahoe