[whatsnewell]

Todd, when you had the engine rebuilt did the shop check out the condition of your transmission while it was out?  I'm pretty sure you have an oil and transmission cooler built into the radiator just like I do, and I'm pretty sure the tranny is an Allison.  It's a good idea to have the transmission fluid checked once a year and the filter changed.  A periodic check of the condition of the fluid will help avoid catastrophic failure.  Frankly, like Michael and others said.....don't blame yourself....it doesn't seem like you did anything wrong.  I routinely keep my RPM's at 2,000 on long climbs, or while in traffic to keep that fan spinning at maximum velocity to keep air flowing across the radiator fins.  Once the transmission heats up it takes much longer for it to cool down than the oil and coolant....at least that has been my experience.....on the other hand the Allison transmission can operate without harm at much higher temps than the 2 stroke.