With no warning my girlfriends 2013 journey 3.6 dropped to 3rd? gear on the freeway and the engine redlined, she pulled over after 1/2 mile or so once it was safe, and now it wont move at all.
I got there with scanner and was greeted with:
p0729 gear 6 incorrect ratio
p0734 gear 4 incorrect ratio
p0735 gear 5 incorrect ratio
p0736 reverse incorrect ratio
p0841 trans fluid press sensor/switch A circuit range/performance
p0846 trans fluid press sensor/switch B circuit range/performance
p0868 trans fluid pressure low
(all codes were pending, still no CEL on)

Fluid looked ok and didn't smell burnt (after finding out there is no dipstick...... _) She said it wasn't making any noise, but when I got there hours later after work, it had quite the whine in park that went away when shifted into gear.
It wasn't slipping or shifting weird. Absolutely no warning. Not even sure where to start.
Any advice besides take to a shop for rebuild? I am a mechanic but industrial more than automotive, so trans diagnostics aren't my wheelhouse.

 

Shop time.

 

lol probably whats wrong with mine. its a dodge. thats the problem cant even get 90k miles on it before youre putting a new trans in it like me. lmao