I drained the oil in mine, put it on jack stands, filled with half kerosene and half 30 wt motor oil. Left the halogen light shining on it for a few hours to warm it up. Ran the truck on the stands for about ten minutes. After draining I pulled the inspection plate off of the back, and brushed/ rinsed with kero. Put 'er back together, filled with oil, changed after a hundred miles.
Basically, what Joe said, but I've had a whole lotta coff-ay.
