Just curious here. When I get in my T660 and insert key and turn to the right, and before i engage the starter, what is the truck doing during its "preamble", for lack of a better word? I hear some funky servo sounds and the brakes purge themselves or something. I usually wait for it to complete before cranking. On my personal diesel car I always wait for the glow plug light to go out, but it only takes a second or 2.