I have a 98. 5 that does the same thing one of suncoast transmission . i call about 2 years ago when it did it only in the winter , now it does it every day, they were no help . I park my truck on a hill and it will not stall when its rolling. The only good thing is that the truck will not go some times because the oil drains out of the tc,suncoast was no help with that issue . once i get it in gear without stalling it will no longer stall anymore , even if its only in gear for a sec. i call suncoast back on 5-15-09 and was told that it was not the transmission and that they never heard of this problem