[dv657172]

71 GTO

Numbers matching nearly top to bottom but....rear end looks to be a 12 bolt (posi) and PHS docs dont show a Saf-T-Trak option. Plus car is a 400 with AC which would come standard with a 10 bolt 3.23.

I have looked on front of axle tube on passenger side but cant find a code and differential cover doesnt look like the 12 bolt in my 72 or in the service manual (see pic)

Any idea whether this is just an aftermarket cover or should I look somewhere else for a code or something to id this thing?

I have owned it since 2009 and have previous owners receipts for parts and service back to mid 1980s and nothing shows any rear end work

I know its not likely the correct rear, just trying to id it. Feels like around a 3.23 gear