Hello I'm a newbie to this site so bare with me please. I have a 05 z71 suburban with 180000 miles on it. The other day while driving the check 4wd lite came on. I pulled over and shut the car off. The light didn't come back on. I have never driven it in 4wd.
Well the problem came a few days later when I went to drive off and I pressed the gas pedal there was this loud noise and terrible rumbling come from under the car. It felt as if was coming from the front driver side but I checked and found that it was coming from the back. When I change thru the gears, P-D3, they engage fine. Someone suggested that it was the transfer case motor. Please any suggestions? I can't drive it or better yet afraid to.

 

If your sure it is in the rear of the vehicle, I'd suggest pull the differential cover off, and inspect planet gears. My 2000 had an issue, son is a mechanic, got them replaced before any damage happened.

 

Check your driveshaft U-joints. They go out a lot and make some pretty good noise. Block your wheels and put the tranny in neutral. Get under there and see if you can move it around. usually the rear one goes first.

 

By all means check the u joints, but if you have grinding/jerking on accerlation, I'd strongley suggest inspecting the diff planet gears while it isn't an too exspensive fix.