[Hobbyist4Life]

Hello,

I have a 2007 Envoy Denali that I swapped a L92/6L80E/AWD transfer case from a 2008 Escalade.

It was literally bolt-on except for the front driveshaft which I had to swap out the transfer case end to connect to the new AWD transfer case from the escalade, nothing a machine shop can't do.

I have modified the wiring harness and everything is good to go... except for PCM/TCM communication.

It starts and drives just fine, but the transmission doesn't shift due to loss of communication and I'm at complete loss.

E67 OS: 12611938 (Original OS for the Envoy)
T43 OS: 24239353 (Original OS for the Escalade)

I need help getting the two to play nicely with each other. I currently only have access to HP Tuners. I know a local tuner who has EFILive.

Please guide me as to which OS for which controller to use so that I can go ahead as soon as I find someone who can do OS swap.

P.S.: I live in Qatar

AFAIK, @timg is the go-to for 6L80E swaps but I'm not sure why I can't send him a PM.

Regards,
H4L

 

[Mitch808]

You can’t m him due to your low post count. It’s to prevent scammers and spammers. @timg hopefully can chime in and help. You’ve read his thread on his install and experiences right

 

[Hobbyist4Life]

Yes I have, it seems like I need an 08 or 09 E67 OS.

I'm not sure why an 07 wouldn't want to communicate though?

And what advantages would I get from running an 09 instead of an 08 OS?

Regards,
H4L

 

[jwalker]

Yes I have, it seems like I need an 08 or 09 E67 OS.

I'm not sure why an 07 wouldn't want to communicate though?

And what advantages would I get from running an 09 instead of an 08 OS?

Regards,
H4L

I just got done with a 6l90 swap into my 2007 TBSS. I had to get the ECM flashed with a 2008 OS (12618164) and I'm running the same TCM OS as you. There isn't a lot of info on ECM/TCM compatibility out there but like mentioned above @timg has chimed in a lot on 6l80 swaps in the past. Here is a thread that's filled with good info from him.

6l90 swap with ease!!! | Chevy Trailblazer SS Forum (tbssowners.com)

 

[Hobbyist4Life]

I just got done with a 6l90 swap into my 2007 TBSS. I had to get the ECM flashed with a 2008 OS (12618164) and I'm running the same TCM OS as you. There isn't a lot of info on ECM/TCM compatibility out there but like mentioned above @timg has chimed in a lot on 6l80 swaps in the past. Here is a thread that's filled with good info from him.

6l90 swap with ease!!! | Chevy Trailblazer SS Forum (tbssowners.com)

Nice, that's good news!

Unfortunately for me, none of the local guys with tech2/mdi/mdi2 etc.. was confident enough to flash 08 or 09 software for me and everyone rejected doing it.

Luckily, a friend of mine happened to have a 09 9-7x pcm and gave it as a gift. It's working fine just to get it tuned for my cammed L92.

I am still looking forward to having @timg reply as I would like to have a copy of his tune file so I can get the TUTD working 🥹


Regards,
H4L

 

[sahls01gmc]

H4L,

I’m highly intrigued with this build! Did you use the Escalade transfer case, or your stock one? And is that AWD, or 4WD? A 6L90 is high on my list, but the cost is significant when you add in the ECM and wiring along with driveshafts. How much do you have into this swap?

 

[Hobbyist4Life]

H4L,

I’m highly intrigued with this build! Did you use the Escalade transfer case, or your stock one? And is that AWD, or 4WD? A 6L90 is high on my list, but the cost is significant when you add in the ECM and wiring along with driveshafts. How much do you have into this swap?

Glad you like it, it's AWD using the Escalade transfer case!

The physical part is direct bolt on. The rear driveshaft clears fine, probably because I'm 3" lifted, but I think it would be better to shorten it just a lil' bit. Especially stock height I think shortening it by 0.5" would be perfect!

As for the front shaft, I had to cut off the CV joint from my shaft and weld the portion that goes into the transfer case from the escalade. I simply used tape measure and machine shop did the rest.

I rewired the harness by myself. It wasn't too bad but definitely had to think about a couple of things, mainly the P/N switch wiring for '09 OS (no meed to replace ECM, just get it reprogrammed for '09) while also having the shifter interlock functional... Had to add a weatherproof relay for that which I mounted in the original TCM location.

I can't tell exactly how much I got into this, I got the whole Escalade (totalled) for around $650, got the engine rebuilt along with a TSP L92 stage 3 truck cam and used most of the conversion parts from the Escalade.

And definitely pricing here in Qatar would be much much different from the US.

Oh, and I didn't have to pay for any labour work.


Regards,
H4L

 

[stag0608]

You need to get in touch with Jim Miller at Zero Gravity performance. He can get you set up.

 

[Hobbyist4Life]

You need to get in touch with Jim Miller at Zero Gravity performance. He can get you set up.

Thanks for the suggestion, I've almost got everything set..

Just needs full tuning, and having the time to think about implementing TUTD as I will most likely need it...

Did I ever mention that it's my daily?