Strange sound

[Trey765]

I have a 97 Z71, I bought it about a year ago and have noticed a whine/grinding noise in the rear. I changed out the axel seals and all gears in the rear end look good and no metal found and the rear grease had it's normal stink. The axels are straight. It almost sounds like a brake drag but the brakes are fine. The transfer case is full and everything seems to work fine. I am out of ideas, some people say its just the way the transfer case sounds. I had a 98 z71 in 98 and I don't recall it ever having a whining/grinding noise.


Any ideas what else it could be?

Thanks in advance for the help.

[Trey765]

PS I am new so I have no idea how to make a cool thread. The Z71 is the DD and 85 is blown apart in my garage doing an LS swap 408 stroker.

[bfay17]

When my 88 gmc was making that noise it eventually blew a spider gear up in the rear end. It just sounds like a low growl or a humming sound? Mine was humming and eventually one day just blew up. Im not saying this is your problem but it was mine. Good luck I hope you get it figured out.

P.S i had no metal in my rear end either other than the blown up spider gear.

[Trey765]

Thanks I will look again at the spider gears when I go back into it.

[willett]

at what speed does the noise kick in?

[Trey765]

The noise starts about 35. I also changed the wheel bearings out as well when I did the seals.