2018 GMC Yukon - 89k

[GMCTom]

After just 7 years of ownership with dealer maintenance at the recommended intervals. My Yukon SLT (6 speed) transmission shit the bed on a family road trip at 88,892 miles. No warning. It started to hard shift and then would no longer go into gear 20 minutes later, then the transmission light on the dash showed up. I have never towed anything with it, and it's mostly been used for city driving.
This just doesn't make an sense to me - had it at the dealer for a full inspection, nothing was noted on the report there were any issues.
Anyone else had this or something similar happen?

 

[Joseph Garcia]

Can you post a screen shot of the dealer's report?

Afterwards, @NickTransmissions is our resident transmission expert, and he will chime in with his thoughts and perspectives.

 

[NickTransmissions]

After just 7 years of ownership with dealer maintenance at the recommended intervals. My Yukon SLT (6 speed) transmission shit the bed on a family road trip at 88,892 miles. No warning. It started to hard shift and then would no longer go into gear 20 minutes later, then the transmission light on the dash showed up. I have never towed anything with it, and it's mostly been used for city driving.
This just doesn't make an sense to me - had it at the dealer for a full inspection, nothing was noted on the report there were any issues.
Anyone else had this or something similar happen?

We transmission builders who work on the 6L80/90 hear stories like this all the time...

Automatic transmissions, in general, can suddenly fail. Also, there's no such thing as a "full inspection" when it comes to the transmission short of yanking it out, tossing it on the bench and tearing it apart.

Yours may have been the torque converter which can grenade and destroy the pump, leading to the no-movement (no gear) condition. 88k is on the early side but ive seen them come in with less than 70k and more than 250k...