So about 2 weeks ago my car started stalling at stops, or when I put it in gear R or D. I did the usual troubleshooting and cleaning that's recommended, throttle bodies, MAF ETC. Yeah didn't solve the problem, so my transmission is basically dead torque converter etc. Absolutely refuses to go into gear. So I'm looking to swap in a different used 7AT G37 transmission but the more I look the more questions I have.

1. My car was built 3/13, but a lot of the transmissions im seeing are marked as thru 1/13 and from 2/13. If i did get one of the ones marked 1/13 will there be any major problems or issues? Are they different from the 2/13 and onwards ones?

2. The vast majority of G37 7AT transmissions im seeing are for the X models, AWD. My car is RWD. The back of the transmissions are noticeably different. My question is, if I did get an AWD would I be able to swap my old transmission rear onto it to convert it to RWD?

 

Converting is a no-go. The case is physically different.

As far as the transmissions go there's really no tell tale since they usually lock the TQ or give up a gear.
I would try to stay between 2010-2013 G37 or a 2014-15 Q40 7at (same as G37)

Other than VIN confirming the miles and physically checking the fluid quality there isnt much you can do. Id suggest a place that is willing to offer some sort of warranty.
I have a Base transmission in my sport and never had any issues.

 

You might want to plug your VIN into a site like Infinitipartsdeal and see what exact transmission your car was made with (Part Number). They actually have a lot of different part numbers for the 7AT, they are not all the same like most think.