Originally Posted by mastercaster

while it is nice to have faster heat in the winter, and colder a/c in the summer, those are just added benefits of the high idle. the real reasons for having it are far more important than those. it's to run equipment off of the PTO, and to prevent "wetstacking" (unburned fuel and carbon deposits) from low rpm idleing. prolonged low rpm idle times are just trouble, especially with the new restricted motors.

Originally Posted by BroncoHound

It's nice to have down here in the summertime too. Kick the high idle on and the A/C will get your truck about 5* cooler and the blower motor will blow harder as well. That, to me, is all the reason in the world to have it engaged!

Originally Posted by stickler

Nope, that 1000 rpm idle is stock on all of them. The one they're talking about you have to set via the cruise control. It comes in at 1100, then you can raise/lower it in 50 rpm increments via the accel/coast buttons. It turns off when you touch the brake or turn the cruise off. There's a time delay too, you can't engage it on a dead cold engine. I think it has to run 3 minutes or something first.

Another side tidbit, I'm told that at least on the 6.7's, the computer doesn't register idle speeds above 1000 rpm as being idle time.