Transfer Case Fluid Change

There is evidence that changing T-case fluid every 12 months / 12k miles may not be often enough, particularly on low-mileage trucks.

Based on discussions with various people, I would recommend changing the T-case fluid every 3k miles for the first year, regardless of fluid condition. (AMG recommends changing the diff and hub fluids after the first year, and only as needed after that -- new gear boxes tend to have more wear and particles in the first few months / miles. It makes sense that this would apply to new T-cases as well.)

After the first year, I would recommend sampling the T-case fluid at every oil change, and replacing the fluid if it is dark, burned, or otherwise contaminated. This will likely turn out to be every 6 months / 6k miles, but each truck is a bit different.

Filtering fluids (i.e. transmission) significantly prolongs the life of the fluid. For those with separate T-case cooling circuits, adding a filter to the circuit is a great idea. On my last T-case service, the fluid came out nice and pink, just like it was when it went in. (I do have a filter in my cooling circuit.)

Dave B.