Well, the great news is my transmission runs like new again, I don't need a new one! I had it flushed and filter changed. There were no metal shavings or debris in the pan, it was super clean.

Changed the plugs and wires as well. The right rear plug is tricky but if you unfasten the wheel fender, you can get right to it.

 

New fluid works again! Nice work finding a shop to properly flush/filter change! Many others get suckered to replacement?

 

Yes, they're a reputable shop, as reputable as can be for a dealership anyway.

Indeed! Still trying to figure out the "Replace Liftgate Fuse" problem though. They initially said it led back to a relay in the passenger's side B post (which I had no idea existed). I replaced it but nothing. It's going back in next Monday.

This problems seems to be without an answer across the web. All know is that all my fuses are fine, the hatch does not lock and the rear doors do not lock either. I have no idea what else to check.

Any other thoughts?

 

If a short to ground is present on the liftgate lock relay control circuit, the liftgate lock relay will be energized and the liftgate lock actuator will be held in the lock position and will not unlock.
If an open condition is present on the liftgate lock relay control circuit, the liftgate will unlock but not lock.
The BCM will send a class 2 message to the driver information center (DIC) indicating that a fault has been detected and the DIC will display REPLACE LIFTGATE FUSE.
An open ECC fuse
An open or short to ground in the liftgate lock relay battery positive voltage circuit
A faulty liftgate lock relay
An open or short to ground in the liftgate lock relay control circuit
A short to ground in the liftgate lock actuator lock control circuit will open the electronic climate control (ECC) with a lock command