Any good grade of Hypoid gear oil (Mobil or Quaker State) in the rear end will be fine for most applications, unless you have some exotic gears back there, or you have limited slip which requires a special lube. Check owners manual or check with dealer. You can't go wrong with what MBZ recommends..
[Edited by jeffsr on 01-31-2001 at 08:34 PM]
2000 Dodge Grand Caravan SE
No matter what you fix, there will always be something else to fix..
"Warranty" is just another way of postponing the inevitable.