Case differance's

The 741 is plenty strong but you will find more parts for the 742. I have a 741 in my car and it took several tries to get the correct diameter pinion shims. Wider variety of new gear ratios available as well. I like my 741, found a used set of 3.23s (not available new) and installed them on an Eaton TT dif. It's what came on my car so I am keeping it.