4 Wheel Drive/SUVs: 2000 Grand Cherokee, wheel drive vehicles, transfer case lever

Question
I have a 2000 Grand Cherokee and have had an issue where I hit about 75 miles per hour I have a vibration in the car that comes from the front driver side, this happens only under acceleration, if you let go of the gas, the noise stops. I have brought it to the Jeep dealer and originally they thought it was a brake issue or a tire that was out of balance. But today they called and said my transfer case was bad and would need to be replaced. What do you think.  

Answer
Krista,

I would advise you to take the Jeep to a reputable shop that specializes in 4 wheel drive vehicles.  This type of problem can come from a bad wheel bearing, a bad universal joint on the drive line, or an axle, and, to a lesser degree, a bad motor mount or transmission mount, along with tire problems.  If you are driving in full time four wheel drive (usually found in V-8 models) than there is a possibility that the transfer case may have a bad bearing, but this should show up at slower speeds also.  If you are driving one with the six cylinder, then you should have a 2 wheel drive position on the transfer case lever.  If you are experiencing this vibration in 2 wheel drive, then the transfer case should not be the problem.

Carl