Originally Posted by FLavionics
So my new to me DP is rated 360HP @ 2400RPM
and 800 ft-lbs @ 1800RPM.
When climbing a mountain would it be best to stay at maximum torque by manually shifting which would be 1800RPM?
And what about descending
I have a 2003 ISX 380 HP Cummins and 6 spd Allison tranny in a 40' Revolution pusher. I called Freightliner with this question. They said when climbing, keep the RPM between 2000 and max governed RPM. The reason is to get max cooling air from the fan(s). That is to keep the exhaust manifold cool as possible else it can go cherry red and damage the manifold gasket over time. It also cools the water better (more fan RPM) which is my limitation on a long climb.
For descending, I get speed down at the brow of the hill so the engine can hold it with exhaust braking and minimal foot braking. Save those brake shoes! Shift as needed for your desired speed. Too fast and the engine will not hold you.