You can do this maintenance yourself as the only thing you'll need besides the fluids is a piece of hose and a funnel (for filling the transfer case/TOD). Clear Tygon or Vinyl hose is fine, just make sure it's large and flexible enough to slide over the funnel spout. You can use the same hose on the spout that's on the gear lube bottle for squeezing it into the diffs too. There's pics of the drain and fill points in my gallery as well.