i know the idle on the 24v is computer controlled but what info does it use to set the idle and can anything be done to change it threw a computer at the dealer or something? over the past year my truck has gone from about 550 all the up to about 875 now, and for a 5-speed that seems a little high

 

Mine has idled around 875rpm since '04 except when the original VP44 was on the way out then it would idle 1000rpm then slowly reduce to 900rpm.

 

875 is about right for the idle speed. Where did that 550 come from? Nothing has idled that slow from the factory .

 

it idled at 550 when i bought it then it slowly climbed up to 875 over about a year time.... maybe i unbroke it??

 

Yeah, or maybe the rings are seated now.
These things can be much like women...don't try to understand them, jes' appreciate them.

 

First I've ever heard of way low idle?? But you in good shape now! 875 is just right. No manual adjustments anywhere. There is a 'high speed idle' under very cold conditions but not adjustable or selectable.
To get to 55o rpm, maybe your SB clutch was not fully dis-engaged?
RJ

 

If that was the case, I would think the lug sensor would compensate and add more fuel. Step on the brakes gently while truck is in 1st gear with clutch engaged. Lug sensor will add fuel to keep engine above idle if everything is working correctly.

 

Was just guessing. I have an automatic. What do I know.

RJ

 

it idled at 550 before i put the SBC in and before the old clutch crapped out. it runs even better then it did when it idled at 550 so i guess the $110 oil changes and the TLC made it come around. i took alot of time and money making sure i tackled all the little stuff before i started adding power. i just gotta find time to rip the tranny back out to fix the leaking input shaft seal

i have the high/3cyl idle enabled and those work awesome. the first time you hear the 3cyl tho you just bout **** your pants

P.S. anyone know if that valvoline premium blue fully synthetic 5w-40 severe duty cummins recommended stuff is worth 36$ a gallon?

 

Myself, I would go with a higher quality conventional oil before I paid that kind of money for synthetic.
FWIW, Deere has introduced a 0w-40 full synthetic version of their plus-50 engine oil. Dont know what it costs right now but I will find out monday.