2015 Silverado 3500 & 19000lbs

lets see, one has about 25K lbs total wt, with say 90 aq ft of frontal area, about 150hp to go 60 on a level. Then an additional 60 or so per 1% grade, so a 5% grade needs 450 hp to hold 60 mph........which of these rigs has 450hp?

any way, not surprised ANY of the big 3 diesels trying to move 25K lbs is in the 40 mph range frankly! None of them have the HP to hold a hill like that at 60 mph.

Marty