6 speed trans/torque converter failure - 2017 sierra

[MacSauce]

Truck was shuttering a little, almost felt like it was slipping saturday driving in the city, highway fine. Sunday morning there's a whine from the front of the trans at idle. 5 mins down the road the trans/engine revs are jumping all over the place catching and slipping or shuddering till eventually something let go and it starts to coast with the engine reved up. No movement in any gear, engine revving fine, just no power being transmitted in fwd rev or low. Gets towed to the dealer sunday and monday they say its moving fine at least in the lot, they haven't looked into it further yet. Any ideas on what would cause this? It wouldn't even try to move and the next day its moving fine. Also any TSBs with the torque converter or 6 speed trans that might be related? If it is the torque converter do they rebuild the trans as well or just try to flush the debris out?

 

Fortunately its still under warranty (just) but, I like to be informed. Also don't want the trans to go 20k down the road when its out of warranty because it was contaminated. Truck has 145K KMs on it.

[M1ck3y]

There's a number of tsb's that could be related to this. Use the right words on google and you'll find them.

 

If the truck truly is driving fine, I would guess it's some kind of computer glitch. But based on what you've described that doesn't add up.

[MacSauce]

Dealer got back to me yesterday. Shavings on the dipstick so they said it needs a new trans, waiting on GM to approve the warranty claim now is what I'm told.