Does the truck roll freely on the ground if you push it with the motor off? If not, I would say you have something binding up. If it does roll freely, I would reset the motor to the factory setting and retune. Did you happen to get a temp on the motor to see if it was really hot or really cool when it bogged down?

Also, check your fuel system for clogs. Rinse out your tank and your fuel filter. If you have been driving in dusty environment, it wouldn't hurt to remove the carb and clean it out real good.