I believe I found out where that smell is coming from. On the left side of the radiator about 6 inches down, there is a rubber hose attached to it. The rubber hose has a cap on it and the hose runs down the side of the radiator and back to the differential. (This isn't the tube that runs back to the radiator reservoir.) There's nothing leaking out, just that odor. Is there anything I can do? If it's overfilled, should I remove the cap and let it drain out? I saw on a GM website that this tube should be turned down at the end, forming a upside down u shape. Mine isn't that way, so could that be the problem?

Any help is greatly appreciated.

Thanks,
Rich

 

Is it the front diff. breather hose?

 

Yep, that must be it. It has a cap on it, and the smell is coming from it. No oil leaking though.

 

hopefully not burnt gearlube......better check the differential level and fluid condition....dip finger in and look and sniff to makes sure not dark and burnt

 

X2!
Gear oil does smell funny to begin with but you shouldn't really smell it from the breather unless you have some issues.

 

It seems to be going away. This is one week later. I had a new transfer case put in and they filled the diff while they were at it. I think they put too much in and that's why it smells. If it doesn't go away completely, I'll take it to the shop. It's running great. Thanks for your input.

 

:wall: #@*&!! I was driving around with it locked in 4 hi. The dash light indicated 4 hi, not locked, but when I backed out of the drive I turned the steering to the right and it felt like the brake was on. Backing out and turning the steering to the left felt normal. So I drove up the street to a gravel parking lot and got it to shift to 4 hi by backing up and turning. Now the smell is almost gone when I drive and it turns easily. Doesn't feel or sound like any damage was done. The diffs were just gone through and synthetic gear oil put in. A new transfer case was just put in too and that may have saved me from disaster. Good Hummer :-)