He's got a manual. Must have steeper hills than I have in Colorado?
I climbed it as fast as I "could carefully" without driving off a cliff to see how an auto could go up and over a mountain. My ears popped like crazy.
Driving with this post in mind I stayed no more than 2200 RPMs, constantly accelerating uphill because I needed to with all my braking and my ears popping. My truck was empty, unloaded, and not pulling a load which it usually has at least one going against it.
My RPMs are exaggerated as I was having to constantly lower my expectation of speed a little so I didn't go off the cliff. I was usually crapping my pants on the brakes.
Short story long, a 2.7 can accelerate nicely up a grade and still maintain an economical RPM IMHO. As long as I just had my foot maybe less than an inch pressing the accelerator my TCM would gear me down actually, and I'd accelerate.
I've tasked it pulling a load before for a longer period and it was different. I think I'll do it again being more controlled.