Help please - Grinding sound from transaxle while reversing

[truegearhead]

Check the output shaft covers. When I used to autocross my car (hundreds of clutch drops with track tires) I ended up cracking one of the covers. Oddly it didn’t leak but the crack created an edge for the drive axle to grind on. Oddly I now I have a new grinding with a different transmission 5 years later. It only grinds going forwards and doesn’t grind when the wheels are up in the air. Probably once again a transmission problem. The 2.5L transmissions aren’t great for taking abuse