4.10 upgrade problems

[05Trailr]

Like it says, I have an 05 2wd 4.2L came stock with 3.42s . I with 34s it just wasn't working, so I found a complete rearend with 4.10s and PCMofNC do there deal, put it in and test drove and saw right away it was awesome, then the ABS & BRAKE lights came on the cluster , also the cruse control will not even try to work. I went by 2 local GM dealers to see if they could do a relearn or whatever and tell it it had 4.10 gears, well they almost freaked out on me saying that it was illegal !! haha and the GMC dealer said even if it wasn't "illegal" they probably wouldn't be able to do it because it was a chevy and not a GMC ! So at this point I'm just dumbfounded by the excuses I was getting....so if anyone could point me in the right direction please let me know. Thanks in advance!

[Diacom]

Sounds like both of the local dealers are probably not places you would want to return to. There is another member with a file or a link for 4.10 gears but it is for a 4wd. I am not sure if that will matter or not in this case, but it might be a step in the right direction.

It seems odd that the cruise does not work however. I have 4.56 in mine from 3.73's and the cruise works fine as long as the Speedo reads over 25mph. And I do have the ABS & Brake lights come on. I pull up on the Ebrake handle one click then release to get rid of the ding and just deal with the lights for now.

I'd try for a non local dealer and see if maybe they are more willing to help you out.

[Trail X]

Shadowdrgn (or a spelling similar to that) has a file programmed with 4.10 gears that may work for you. You just need access to commercial programming software.

Mine didn't want to let the cruise control work either. The trick is just to pull the J fuse for the ABS module in the hood fuse block. Your ABS won't work anymore, but it isn't going to anyways with the swap. It makes the cruise work again and also gets rid of the annoying ding.

[bartonmd]

So glad I have an '07...

Mike

[HARDTRAILZ]

So glad I have an '07...

Mike

As I am to have an 06

[v7guy]

IIRC in some cases pcmofNC has been able to rectify the issue, but not always, it seems to be a crap shoot and there's debate as to why it works sometimes but doesn't others. Push comes to shove you should be able to find an 05 pcm that came with 4.10s and go that route.