Just like a little backdrop information on my Dana 61? I have a housing no. D8TA-AFA, 603899-1. I wrote down axle code as 221 but only find something meaningful for 22.

Like to know what the code numbers mean, D8 I know is '78, TA would that be transmission automatic? If this is a Dana 61 is that desirable, is it as reliable as a Dana 60? How many spline? I wrote down 10 bolt is this correct? When someone says 9" rear end what is the significance and comparable to mine? Any help on this appreciated.

Just learning