Wanting to buy a truck to do loads for the mountains (EX Colorado/California areas)

The biggest darn motor you can get, my friend. Pretty hard to kill a series 60 Detroit., no less than 500hp.

 

Cummins N14 525hp with 18sp. Hard to find them though

 

Aint no mountain high enough to hurt a CAT.
Get ya something w/a 18spd for sure-so you have control.
As stated above-no less then 500 ponies.

 

500HP and 3.70 gears and a 13 speed minimum for 80000lbs. More than 80000, go with 3.90 gears and 525-550HP and an 18 speed. The truck will be strong enough to change the rotation of the earth.

 

wow you guys, really setting him up for failure.

To the OP, learn from your friend, don't buy a truck unless you know how to buy one. Most don't and most break down and get in over their head with money.

There is a process, go look up here dyno test on this site and you will find a lot of posts with the info you need.

 

I use a 550 hp D16 Volvo 780 with 3.08 rears and a 12 speed I-shift. I pull the mountains west of Denver often and have no trouble.