I understand this is a common problem.
The tranny just went out in my Saturn, with just under 90,000 miles. Under miles but over the 10 year warranty.
The fluid is burnt and stinks. The tranny whines, goes in and out of gear. After a short drive it will not engage into gear, after the transmission cools it will function (normalish) for a short time. Had to have it towed home but I drove it onto my ramps.
I’m prepared to swap the tranny myself in my garage. I’m not afraid of the work ahead of me. From what I’ve read the computer will need to be reflashed. Is this correct? How can I go about doing this?
I’ve found reman units for $2300. Good price?
Any tips or suggestions would be greatly appreciated.
Thanks

after using a scan tool I had these codes
P0796
P0700
P0752
P2723

 

Let it go.

I had a 2008 Vue XR with the glorious 6T70 tranny.
Mine was rebuilt (not replaced) on GM's dime at 93K. 35R waveplate issue. You already know the deal.
If you haven't trashed the entire tranny, in theory you could keep it in tapshift mode and use it in 246 only --that is if the TCM will let you start from 0 in 2nd.
If the vehicle is moving it will stay in 2nd gear as long as it can but is programmed to downshift to prevent stalls and bogging, Faking it out by keeping the rpms up a tad may delay the downshift (guess).

Anyway--one of the biggest reasons to not attempt the tranny swap is that you do NOT know if you are getting a unit that has already been repaired or a timebomb like the one in your vehicle.
ANYONE in the know will tell you it's a unit that has already been repaired. The fact that they know about the issue means they know how to answer.
I do not believe you can tell from the outside, as from what I've been told back in the day by experienced Satty techs is that most of the internals must be removed to access the waveplate, and that the 35R clutch is usually trashed as well.
So if you look in there, all the seals are new as they are all replaced when things are reassembled.
Additionally, you are at the mercy of the person who did the rebuild.

Oh, if the shrapnel from the fracture od the waveplate gets circulated within the tranny, you're looking not just at plugged passageways in the tranny (doesn't matter if not rebuilding) but potential torque converter damage/replacement.
And if the tech didn't flush the torque converter, the rebuilt tranny is welcomed with waveplate shrapnel as soon as you turn the key the first time.

Then there is the issue of metal brake lines corroding prematurely even when the system is properly maintained, brake lines collapsing by the calipers, leading to the pads not retracting from the rotors. Incredibly dangerous.

Don't get me wrong -- I loved the way it drove, handled, etc. (I totaled mine in a 3mph rear ending on an on ramp.

It's 11 years old
Part supply will only dwindle
Yes the chevy captiva was born from this vehicle....Do all the parts from the 1st gen captiva fit? No clue

or take a $3k gamble. If you do, do your homework and figure out how to tell a rebuild from a timebomb. Just because it came out of a running vehicle does not make it ok. And stay away from the lower mileage trannys -- most of the failures occur 80K and up. a 50K 6T70 is almost guaranteed to be a timebomb.

Please return to let us know how it worked out/your decision

Msybe ask a chevy dealer who they send their tranny work to and find out from the tranny shop how they "mark" the tranny so the next guy knows it's been worked on and for what. I collect vintage pocketwatches; anyone working on them engraves what they did (in "code") so the next guy knows what in the watch has already failed.

I would put that $$ towards another vehicle