I put my 3k stall in my 08 RCSB with a 5.3. Had Nelson tune it for the stall. I sent my PCM back twice so far because while driving around town I constantly lock/unlock the TCC. I've had him adjust speeds, throttle input, etc... I think my problem may be that I have 3.42's with this stall and my lock up at 38-40mph. I don't think the PCM likes to lug this low rpm locked up? I don't know what to ask for or adjust to get it to work? Should I just make the lockup at ~50mph to avoid the whole thing around town? That will kill any mpg's I had, but there no good now with the locking/unlocking. This is starting to get nerve racking.

 

You need gears. It's going to eat your gas mileage crusing around locking/unlocking. My factory stall locked/unlocked with 3.42s. Go with 4.10-4.56. You won't look back.

 

The 3.42s are killing you. You have the right idea if you don't want to do anything with your gears; just have the lockup adjusted to 50 mph and it should help considerably.

 

I spent weeks tweaking the lockup tables for my stall when I got it. Having it not lock up until about 50 will definately help.

 

yea def ur gears are killing u i only have a 4.8 with a 3k stall and i have it lock up at 38 and i can easily push it up to speed without unlocking even up hills with the 4.56gears !!!!!! hell yea !!
the way it went for me with 3.73s the power u feel at about 50-55 now i feel right when it locks up at 38 as far as getting it to move without bogging alot hope this helps

 

what size tire u running?

 

It doesn't really bog, I don't mind lugging around. It will do this even just cruising flat with minimal throttle. I don't think the hills of western PA help either. I may just go 4.10's. It just seems there has go to be some way to tune this to work. If not, I'll just put it to ~50.

 

o yea theres def a way to tune it to fix the prob because the converter didnt change the power of the motor once it locks up it should be the excactly the same as stock he just has it to sensitiveto unlock under low rpms

 

Well; what should I be asking him to change, to make it work? I am new to this stuff and can't begin to know how many tables there are in the PCMs. Oh, and the tires are 30.5".

 

Just have him up the lock up to 50 mph. That's where it's set on mine.

This issue you're having is also the same exact reason I recommend EFI live or HP tuners be the first thing anyone buys. You could have had this issue solved already. You also could have the trans tweaked to exactly how you like it. You'll never get that on a mail order tune.