Diablosport Forums

I have a 99 seirra 6.0 I can't seem to get the 2nd gear shift right. It really hits hard if I'm half throttle or beter and I mean break you neck. If I put a stock tune in is fine. The touqe mang is on as well

what is the revision?

9r

brody1 wrote:I have a 99 seirra 6.0 I can't seem to get the 2nd gear shift right. It really hits hard if I'm half throttle or beter and I mean break you neck. If I put a stock tune in is fine. The touqe mang is on as well

I have a question since I'm having a similar issue with the tune installed. Have you scanned the PCM for codes with the Predator? And, if yes, are you getting a P0748 code? This code is for an electrical issue with the Pressure Control Solenoid.

Mine shifts hard like you are talking about but only after I've had a WOT event like when passing on the highway. It goes away with the next ignition cycle and all seems to be good again, except, there's this code lingering in the PCM all the time. Right now I have the stock tune in the truck and I can't get this code to trip again. I'm thinking the problem is in the Predator tune I'm using.

I'm curious where this thread will lead.

No I don't get that code its just very stiff shift to stiff

Same thing with my 07 silverado when using the pretuned diablo tune. cant seem to figure it out and no one knows anything bout it. thinkin of having lew do a tune and see if it goes away but would hate to spend the money if it doen't

Found out that if u back off pressure in the wot setting it can be fixed. Even though I'm not wot the programer still things it is and it did it

Found out that if u back off pressure in the wot setting it can be fixed. Even though I'm not wot the programer still things it is and it did it