What gear for hills?

[NVWolfer]

So in my other truck I turn "OD OFF" when taking a steep or long grade. Makes it so the transmission doesn't heat up and keeps the TC in the trans locked up.

Would I be better off with the tow/haul button used or should I be dropping it into 3rd to keep the TC locked up?

 

[DWTahoe]

I've just been turning on the tow/haul mode when I've been on the mountain passes. Seems to keep it from hunting for the right gear and has been working out well for me.

However, on the downhill side I turn it off and use the manual select for the right gear. I'm pretty sure the tow/haul mode will still ride the brakes and I don't like how high it revs the rpms. Mine does weird stuff on the downhill and I don't like it at all for that. I do all this without a trailer, so, it may work a lot better if I was actually towing something.