I just read down through this and was wondering if the stat was a higher temp rating. I also wondered if you downshifted on the hill? If you allow the rpm to fall too much the cooling fan will not cool the engine properly....sounds like you are on your way to getting it all tip top.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.