Thats why they put the Towing Capacity in the Owners Manual! Its there for a reason, not to spoil your fun. Yeah an oil cooler is great but there is a whole lot more that a heavy trailer effects on your vehicle. Automatics (especially light duty) are only designed to pull so much. A heavier truck has a heavier tranny to handle the extra loads. Check out the Tundra! Big difference in the design of one AT and the other. Be sensible people. "Respect the Vehicle." M. :twisted:
do you think it happened because of the trailer?
because during the winter, especially when is really cold I have the same probl;em, AT doesnt want to shift to the up gear even the engine warm up more than enough (10-15 mins).
and why it happened right away I replaced the AT oil?