Proper Shifting to Reduce Engine Temperature
I have had my RV for 12 years and I think I learned something new. From the very first month I had the RV I experienced overheating when traveling in temps over 100 degrees outside. I have a CAT C...
Forum Discussion
DrewE wrote:wolfe10 wrote:
Bottom line: It takes XX HP to climb a grade. If you generate that HP at 2000 RPM instead of 1600 RPM, the FAN and WATER PUMP are turning 400 TIMES A MINUTE FASTER.
It takes xx hp to go up a hill at a certain speed. At a lower (vehicle) speed, it of course requires less power. If by downshifting the vehicle speed also slows down, you not only have possibly more water and air flow, but less heat generated by the engine as well--a double improvement.
These two posts are spot on. Another way to describe it is that it takes XX amount of "work" to get your coach to the top of the grade. By using a lower gear, your engine gains leverage against its connection to the ground reducing its work load, and since you go slower, the work needed to get to the top is spread over a longer time period so the cooling system has more time to get rid of the heat that is generated getting to the top. On one long, steep grade I found myself all the way down to first gear to lighten the load on the engine and to spread the remaining load over a long period of time.
