Just out of curiosity, does anyone know what the rev limiter is set at on the 6.7? Because more than once I have accidentally put it in manual mode instead of drive and one of the times I took off pretty quick and soon figured out what I had done when I noticed the RPM's were way up there. I don't know how high it got but I know it was well past 3,000 rpm. All I can say is that they do seem to rev pretty fast.

 

Even in manual mode, the transmission will shift before the engine reaches the RPM fuel cut off limit. Going over 3,000 RPM's doesn't hurt anything.

 

That's what I thought too, but when I noticed that it didn't shift I looked in the manual and it says that in manual mode it will not automatically upshift even if the engine is approaching the RPM limit.

 

I have noticed that it will rev pretty high to try to slow the truck down when I'm towing something in tow/haul mode and going down a hill ( which kind of worried me but I guess its normal) but I was just curious as to what RPM it limits it to when you are actually on the accelerator and giving it fuel.

 

only one way to know for sure.. get out there and find out for the rest of us and report back...

 

Hi nxtdiesel, when in Manual mode the truck will not upshift but will eventually hit the red line and fuel will be cut off to prevent engine damage. Manual mode will not allow you to downshift to a point where the engine would rev above red line and possibly cause engine damage.

Keep in mind when the transmission automatically downshifts to slow the truck down (whether because of Tow-Haul and/or Engine Brake selected) no fuel is being used if your foot is both off the gas and brake pedals. Interestingly, the Duramax will allow the engine to go above redline during engine braking events with no fuel being used. I don't think the Ford will.

Just be aware that this engine is entirely computer controlled and the computer will not allow you to do anything that would harm your engine.