Ok I smelled a little rubber burning last night when I went to Wal-mart with my son. I did get on the gas like a fool to show of a little bit. It's a dually, 3500 1993, L80e tranny 6.2 dieselchugger. Any clues on why I'm getting a humming noise only when in gear? It is not loud, but I know it's there and it wasn't. THANK YOU IN ADVANCE!!!

hummm a little more info would help..where is this "humming" noise coming from as far as you can tell..engine trans or differential

might be a dead motor mount. and when the trans is in gear the engine leans over a bit untill the 2 metal pieces touch and then it makes a humming sound up the frame.