Auto Transmission Usage

This is probably a dumb question, but reading the owners manual got me concerned. When I'm driving up and down mountain roads, I like to use 3rd or 2nd gear on the auto transmission to keep the rpm at about 2500. This gives me much more control and response. The manual says the transmission can be damaged by overheating if I do this for an extended time. Is this true? How do you guys drive your Tacos in the mtns? Is it better just to use the Drive setting?

 

I do the same thing b/c it keeps the engine in lower gears and lets your engine slow you down as you approach hills and switchbacks as well as give you more torque go up the next hill. I always turn off O/D while driving in the mountains. The main concern is how fast you are going in the lower gears. The owners' manual has more info on this.