Hey guys, when ive test driven some cummins trucks and had them on cruise, then put the clutch in to slow down or whatever, then engine will rev up between 200 and 1000 RPM above what the cruise RPM was at, this only happens whe you push the cutch in, not when you hit the brakes or hit the cancel button on the steering wheel, does anyone elses truck do this and what causes it. Also, is there a fix to this so i am not always worried that i will over rev the engine when downshifting from highway speed (its gotten close to over revving on one truck)

 

They all do that.

The cruise will disengage when you push in the clutch. The problem is that the time it takes for the cruise to disengage, the engine will rev before the cruise cuts out.

Try it on a hill while your pulling and that will open your eyes!!!

If you know your going to downshift, hit the cruise cancel button first, then it won't do it.

Jeff

 

ok, i can imagine doing that uphill on a load....i bet it hitd the rev limiter....haha