# exchange auto transmission 6T40



## downunder (Mar 3, 2018)

i am constantly concerned about the life of my 6T40 six speed auto that is driven by my 1.4 turbo 
i am aware of several that have let go even early in life at low kms
my understanding is that GM is aware of this and extended the warranty in oz to 150,000 not as generous as the US im afraid
i change my transmission fluid regularly with the specified synthetic oil, but as i am reaching 165,000 km on my cruze my odds are the day is approaching
to exchange GM 6T40 in oz reportedly can cost upwards of $6000 AU.
i have been told its a two day job getting it in and out.
as i have a good mechanical background i am curious if its a job i could actually contemplate but i have been unable to find any info or tutorials outlining the procedure in detail.
any leads would be most welcome, i just want to check it out! its most likely out of my league anyway.
cheers
downunder


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## jblackburn (Apr 14, 2012)

The pre-2012 6T40's have a higher failure rate than the 2012+ models (at least in the US). The transmission was redesigned with several changes at that point to improve longevity, shift quality, and fuel economy. Any 2012+ 6T40 should swap with any 2012+ 6T40. The earlier years are a bit more questionable; I'm not aware of anyone that has gone "Gen 2" of the transmission to an earlier year.


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## Blasirl (Mar 31, 2015)

Welcome Aboard!:welcome:


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## BNoland (Feb 28, 2020)

jblackburn said:


> The pre-2012 6T40's have a higher failure rate than the 2012+ models (at least in the US). The transmission was redesigned with several changes at that point to improve longevity, shift quality, and fuel economy. Any 2012+ 6T40 should swap with any 2012+ 6T40. The earlier years are a bit more questionable; I'm not aware of anyone that has gone "Gen 2" of the transmission to an earlier year.


jblackburn. When you say "any 12+ 6T40" should swap, does that mean that I could put a gen 3 6t40 out of a 2013 Cruze 1.8L into a gen 2 6t40 in a 2012 Cruze 1.8L? I can see several differences between them on the Sonnax page. Will the TEHCM program properly? I'd love to use the '13up as a replacement as they are much less expensive on car-part.com. thanks!


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## jblackburn (Apr 14, 2012)

BNoland said:


> jblackburn. When you say "any 12+ 6T40" should swap, does that mean that I could put a gen 3 6t40 out of a 2013 Cruze 1.8L into a gen 2 6t40 in a 2012 Cruze 1.8L? I can see several differences between them on the Sonnax page. Will the TEHCM program properly? I'd love to use the '13up as a replacement as they are much less expensive on car-part.com. thanks!


The 1.8 might be a different case; they switched to the 6T30 instead of the 6T40 in 2013.

Having not actually done the swap myself, I'd say it would probably be best to match part numbers to guarantee it works. I've only seen evidence to suggest that 2011/2012+ are internally different, though.


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