Question

Is it more efficient to drive fast uphill?

Answer 1

I don't think so, because driving fast uphill will consume more fuel.

Answer 2

Depends on your motor and transmission mostly. A motor is most efficient at the rpm at which it makes peak torque. ... It just seems to me going slow up hill just makes the engine run for so much longer, while going fast it burns more fuel per unit time but for much less time.