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I'm going to do some research and see if Fords with the same tranny have similar issues. If not... pretty good chance it's programming.
Whatever happened to that poster who owned the tranny shop? He had pressure related program changes that pretty much solved the problem IIRC.
 

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I'm going to do some research and see if Fords with the same tranny have similar issues. If not... pretty good chance it's programming.
Whatever happened to that poster who owned the tranny shop? He had pressure related program changes that pretty much solved the problem IIRC.
I've read a bit about it and while the transmissions are similar, Ford uses it's own TECM from what I understand and as you imply, it's own programming.
A similar example exists with the 10 speed. Not sure about the 8 speed or 9 speed. The 8 speed is of a different design though, from what I've read and has it's own issues or at least did till a different fluid was decided upon.
 

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From what I've read, Ford puts their TCM outside of the transmission. The rest of the TEHCM is surprisingly similar.
 

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I had misgivings about the 6T75 transmission all along, from the shiftiness, to the delay in 2-3 shift, even rpm flares. It's something I learned to tolerate. I maintained the transmission as recommended, too. It never failed me through 130K+ miles - not even the 3-5-R waveplate. In 1500 miles, I've found the Caddy's 9-speed 9T65 to be a vast improvement.
 
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Yeah, if it is a program thing, it hopefully won't lead to failure.
 

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Yeah, if it is a program thing, it hopefully won't lead to failure.
They (GM) went through some programming 'growing pains' back in '07 and '08. I had through the May '08 flash done and it improved things a bit, but not totally. I believe that's the last factory programming adjustment done to the 6T75 transmission.
 

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The newer tranny is the 6T70, yes?
 

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The newer tranny is the 6T70, yes?
Probably depends on whether the vehilcle is 6-cylinder, or a 4 banger. The '70 and '75 are essentially the same anyway.
 

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Right! 70 is for the 6, and the 75 for the 4...
 

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Right! 70 is for the 6, and the 75 for the 4...
Just the opposite. Higher number suffix almost always means the transmission is 'heftier' - can handle higher torque and horsepower.
 

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The newer tranny is the 6T70, yes?
I can verify that externally, the 6T70 that was in our 2015 Equinox is not physically the same as the one in our 2019 Acadia. The casting and some external placement are not identical. For instance, the fill port location is somewhat different.
Does that make it different inside . . . ? Who knows for sure. I do know the shifting behavior is definitely not the same as our 2015 Equinox with the 3.6L engine drive train. The Equinox shifting was more predictable and had no 2 - 3 flare in the 5 years we owned it.
 
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I'm going to do some research and see if Fords with the same tranny have similar issues. If not... pretty good chance it's programming.
Whatever happened to that poster who owned the tranny shop? He had pressure related program changes that pretty much solved the problem IIRC.
If it were programming, why don't all owners have the issue? I'm at 27k miles in my '18 and have not experienced any sort of flare.
 

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Just the opposite. Higher number suffix almost always means the transmission is 'heftier' - can handle higher torque and horsepower.
The higher number makes sense.
Media.GMC.com site actually shows the 6T70 for the 6, and a 6T50 for the 4 for 2019.
Screenshot_20200927-181753_Samsung Internet.jpg
 

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If it were programming, why don't all owners have the issue? I'm at 27k miles in my '18 and have not experienced any sort of flare.
The learning part I think could explain why; so a matter of driving style and environmental. Plus, not every 2019 Acadia has the same valve body, PCM, etc. from what I can find.
 

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The higher number makes sense.
Media.GMC.com site actually shows the 6T70 for the 6, and a 6T50 for the 4 for 2019.
Cool! 2017 shows the same thing. I don't know if anyone ever posted that 'hard-copy' information here during the 2nd Generation introduction.
 

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Yeah, maybe for others sake, here is the GMC media site: ...
I'm disappointed to see they didn't list the Acadia Limited for 2017. Many are still confused about that one!
 

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Maybe you have to find a specific link for the Limited.
 

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I'll leave that to others. At least, the Limited owners manual is available.
 
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