[mickey.1430]

First we were told that regular oil was OK and that the tranny was filled for life. Nothing was said about diffs or transfer case. Now MB is in litigation about the oil story, and, I supect, will soon be in litigation over the tranny story. Personally, I switched to synthetic at the first change and do not burn oil. My tranny went out at 95k, oil smelled like a mens locker room and the fix cost about $6k: thank you MB for the extended warranty. Do I believe the rest of the fluids will last forever. Sure, but only on paper. And that is why I did a diff and transfer case change at about 110k. The cost is very small, probably something like $100-$125US, cheaper if you do it yourself. I have 124k miles on now, truck runs great, engine is just now getting broken in, averaging 21.5-22 mpg on trips and I hope to log many more miles before the model change. Your truck, do what feels right.