Transfer case swap/module flashing questions.

[droptopgsx]

So I have a 2007 9-7x with the 5.3 and after tearing up my 3rd encoder motor in less than 2 years (piss-poor design and brittle gears IMO) and being unhappy with not having a 4-HI or 2wd mode anyway have decided to just swap the 126 t-case for a 226 unit. I know the encoder motor is a similar design but I am hoping that by keeping it in 2wd it won't wear out/chip teeth as fast and if it is really sloppy weather I can keep it locked proper in 4wd vs it constantly turning on/off for miles and miles. I did consider swapping to a case from something older/purely mechanical but I do want the option of the auto 4wd for when the wife is taking it to work in the winter months as she is not used to winter driving and letting the computer decide 4wd or not is one less thing she has to worry about/remember.

I am confident in swapping out the case itself, the front axle disconnect changes and the wiring modifications but what I am stuck on is how to make the computers happy with the case it never had as an option in the saab version.

I have asked around a few places but haven't been able to find a solid answer as to my questions about the class 2 data line and flashing firmware of the t-case module. Basically what i'd like to know is:
1) Can I get a module from a vehicle with the nv226 and flash only my vin to it without messing with the rest of the firmware?
2) It appears like the module I have has all the hardware to control the extra systems so could I keep this module with my vin and flash the proper nv226 firmware?
3) Do the other modules on the class 2 buss even care/have the vin programmed?

I am ok if there is a body code set but I do want the 4wd switch and systems to operate as if it was in an Envoy or whatever, and I don't want the service 4wd light or engine on in the IPC. I don't have the tooling to flash any modules myself, so ideally i'd send it off to get it done but so far the only place i've seen advertising this for non-pcm/bcm modules says they have never tried to do this. If I have to get some hardware to be able to flash it myself so be it, ill do it myself if I have to but just need to know if it can even be done.

I'm new on the posting front but the forum has been extremely helpful in the past for information but I feel that this is not something that many people would want to do so haven't been able to find any information so-far.

Thanks in advance, Sean.

 

[mrrsm]

Sean... Welcome Home, Brother... First... Since you do not presently own an OEM GM Tech2...or one of its "GYMKO" (General Motors Knock-Off) Clones right now...Would you like to get one? As you've explained... in order to diagnose and tinker with the exotics of 'flashing' the Transfer Case Module... you'll need one for making checks/adjustments/Passthru Writes, etc. S0 if you WANT one that comes as a Full Kit (without the case) and it will NOT break the budget at $330.00 with Free S&H. visit aliexpress.com after reading this Post Message:

https://gmtnation.com/forums/threads/new-complete-kit-gymko-gm-tech-ii-scan-tool.17878/post-556060

Next ...if you are looking to put "More 'Chunk' in Your Junk" as far as getting stronger Transfer Case Innards... Check out this excerpt from the linked Article since this might be an alternative choice as well:

"A Beefier Transfer Case borrowed from the Cadillac Escalade’s AWD system offered better on-road control than the Trailblazer’s stock two-speed transfer case."

https://www.topspeed.com/cars/car-n...-engine-gm-s-42-liter-atlas-i-6-ar174949.html

Your Go-To Source for all things "Tech2" will be @Mooseman and a few others who know the 4X4 Ropes around Module Programming and what either will ...or will not... be possible to help make your ideas into a reality.

 

[droptopgsx]

Just as a follow-up to this if anyone is looking for info in the future, I was able to swap in a module from a 226 truck, and after adding in the appropriate hardware/wiring for the electric brake in the encoder motor and the motor/feedback sensor for the front axle disconnect the system works great.

There may be vin mismatch codes, i'm not sure as my higher level scan tool is broken but the service 4wd light is off (no error lights on anywhere) after a lot of chasing my tail I found that I had to use a 10k pull--up resistor to a switched ignition source to the "4wd low" wire that feeds the ecu(I had just left it disconnected). I don't know if the ecu in this truck monitors that wire, but I don't plan on using 4lo for any length of time so even if the ecu gets unhappy with gear ratio codes or something i'm not worried about it in my situation. I did test 4lo and it does work fine, just not sure if you used it a lot if the ecu would get unhappy or if the wire just changes shift pressures or rpm or something.

Either way I am much happier with this system.

 

[Mooseman]

So did you keep the 126 TC or swap it to a 226? I also assume you used a 4x4 switch? If you did, where did you put it?

Now this is wanting for me to do this mod to my 9-7x before winter. The "slip/bang" part time AWD just sucks. It also probably the cause of stripped intermediate shafts.

 

[droptopgsx]

I swapped it to the 226 t-case. I 3d printed a small housing for the mode switch and just attached it to the side of the center console. I may make a more elegant one later but this works for now.

I do still need to reset the adapt-ready position as the tccm and t-case were from different vehicles so it's a bit tight in auto 4wd but it still works far better than the system I had no control over!

 

[Mooseman]

The auto 4WD is basically the same as the AWD you had before. We advise to not use it for the same reasons.

That is a neat mount. Another possibility is to use the rear wiper control hole if you don't use it or rewire it to another smaller switch.

 

[Helikido]

How many hours does the swap take?