Check engine light came on, and I could not back out of my drive way. After a quick scan I get codes p2757 and p0990. Went to local transmission shop in they quoted me 6k for a used transmission. However they could not tell me exactly what was wrong with mine. Has anyone else experienced these codes.

 

2014 ES 350:
code P2757 is shift solenoid valve SLU Off/On Malfunction
code P0990 is Transmission Fluid Pressure Switch "E" Circuit High

 

How many miles are on it and has the transmission fluid ever been changed? I suspect not and you probably do need a transmission. Replacing those coded parts will not solve your other problems that lead to them failing.
You should call around and get more quotes for replacement with a used transmission. I think $6,000 is too high.
Some of the used auto parts places will also do installations if there are any large foreign car yards nearby.

 

If was me I would 1st try 1 or even 2 drain and fills, along with 1 pan drop and filter change. Do Not do a Trans Flush.

If still a problem search car-parts or other for a low miles Trans, and a good rated shop to replace it for you at a better cost. A few years ago I helped my friend get a low miles tranny for $700 and the labor was only around $600 give or take.