A friends '03 K2500 HD Duramax, Allison 5 speed auto. The MIL is on and the range selector only highlights R, 3 & 1. DTC's P0700 & P0708. I didn't drive it but he says the tranny seems to working ok. Occasionally the "message center" will display "shift range inhibited" or something similar to that. I cleared the codes yesterday and so far the MIL is still out but the range selector is still only highlighting R, 3 & 1.

Steve

I experienced a P0708 code on my old 1997 Blazer 2 years ago, and it turned out to be a shift solenoid sensor which was faulty. It was a 50 dollar fix (at the dealer) and I never had the problem again. I remember when driving, it seemed as if it jumped when shifting gears (it was an automatic). try seeing the price on the shift solenoids (there are 2 if I remember correctly, the A, and the B). It's worth a shot. I took it in to pep boys before reading about that code and they told me the whole transmission was faulty, and it would cost 2000 dollars to fix. I fixed it for 50, so it's worth a shot to replace the solenoids first. (mine was the B solenoid)

UPDATE: The "range select" switch AKA "park, neutral, reverse" safety switch on the drivers side of the tranny fixed the issues.

Thanks for the reply fix,iam having the same issues with my truck right now.:banghead:

Thanks for the reply fix,iam having the same issues with my truck right now.:banghead:


Start a new thread on your problem and give all info.
Engine and transmission and what truck and year and codes and mileage?
And someone will help you