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We have a 2011 Equinox with the 2.4L and the AWD 6T45. I swapped the engine at 150k for a 2017 engine with 11k on it. Only had to change the throttle body to get it work. We have enjoyed 20k trouble free miles (other than replacing the plugged cats from the old engine) and now the transmission has gone out. It looks like we have a Gen 1 6T45 in it. My question is can I swap a 2015 Gen 2 transmission in the equinox if I swap in a Gen 1 TEHC Module? Would I also need to swap the valve body? I can get a Gen 2 tranny for $285 with only 15k on it. That's cheaper than a rebuild kit for a Gen 1 tranny and it would save me a lot of time.

I tried to some searching and can't find any solid answers. I know the big difference between the 2 transmissions is in the TEHC module and the rest of the changes appear minor. Am I missing something?
 

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I don't remember anyone posting that they have done the swap to the GEN II.
GM says it can't be done, I think with enough trial, error, and money you could probably do it.
The smarter way would be to rebuild your GEN I.
Usually the problem is with the pressure switches which is easy to fix.

The 6T40/6T45 has been around a long time and has had many changes.
As you know the 6T40 GEN III has been out for a while now.
Do you feel lucky??
 

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I think rednox301 is right. You may end up doing the swap twice [ old Gen1 --> Gen2 --> rebuilt Gen1 ] The bolt up might be the same, but the electronics may be a problem. The Gen2 TCM may not be able to communicate correctly with the ECM, BCM, ABS etc. And I'm not sure the Gen1 TCM can fit or hookup in a Gen2 trans.
The rebuilt Gen1 might be the better choice.
 

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Do you have the source for this?
Only from the GM bulletins that I have been reading and the 2014 GM Repair Manual.
Read closely the article in the link below.
It's from Sonnax, a well respected company in transmission parts and service.

It reads in part:
"A comparison of Gen I and Gen II clutch regulator valves and oil circuits in the 6T40 shows the changes and that they are not interchangeable".

https://www.sonnax.com/tech_resources/215-under-pressure-shift-quality-pressure-switches-in-tehcm-applications
 

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We have a 2011 Equinox with the 2.4L and the AWD 6T45. It looks like we have a Gen 1 6T45 [transmission] in it.
Huh! Never thought of this possibility. I always assumed when a new generation vehicle came out that it was married to a new generation transmission (even if it was just a subtle change).

So my 2011 V6 (6T70??) could have the same transmission as the one GM put in a 2008 or 2009 Equinox??
 

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Huh! Never thought of this possibility. I always assumed when a new generation vehicle came out that it was married to a new generation transmission (even if it was just a subtle change).

So my 2011 V6 (6T70??) could have the same transmission as the one GM put in a 2008 or 2009 Equinox??
Correct. It is common for the 2008-2009 Equinox to get transmissions from the 2010-2011 and just swap the valve body and the TEHCM. I saw a thread about that and was wondering if it was possible to go from Gen 1 to Gen 2. The bolt pattern on the valve body and the TEHCM is the same, the only question is whether the case side has the same oil channels. Having a hard time finding pictures of those in order to do a comparison. Most of the hard parts are similar between the Gen 1 and the Gen 2 6T45 transmissions.
 

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Huh! Never thought of this possibility. I always assumed when a new generation vehicle came out that it was married to a new generation transmission (even if it was just a subtle change).

So my 2011 V6 (6T70??) could have the same transmission as the one GM put in a 2008 or 2009 Equinox??
We have the GM 6T75 in our 2019 Acadia and it has similarities to the one in our 2015 Equinox, but even externally appears different and has a different filler cap on the transmission and also a longer dip stick attached to the cap.

The filler cap on the Equinox was a flat blade and quite short as I recall.
 

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Yes. . i see that.
The 2nd Gen Acadia is quite different .. .



I was just addressing Coltheros (?) and how things can change even though they call the transmission by the same designation. A 2014 6T70/75 is different than a 2017 -19 6T70/75. They may even physically mate up, but many differences. The TCM would surely be different and not sure the rest of engine control module would "accept" a newer version.
 
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