**r*a*n*t**

A factory 8.75 and factory Ford 9" have essentially the same strength. The advantage the 8.75 has is it's higher pinion position, it's more efficient than a 9" and hence eats up less power. The biggest advantage of the 9" is everyone makes parts and complete axle assemblies most of which are much stronger than any 9" that came from the factory.

The D60 is about as bullet proof a rear end that you can get. It also is not as efficient as an 8.75. One of the mopar rags did a back to back comparison of a sb Duster with an 8.75 and D60, the D60 car was consistently .1-.2 seconds slower in the 1/4. Mother mopar only put the D60 behind big block 4spd cars as the stock rear, the others got an 8.75.

The 8.25 was the replacement for the 8.75 and has been in production longer than any other mopar rear (still in use today in Dakota's and Jeeps). Though ultimately not as strong as the 8.75 it's still capable of supporting a sb well past 400HP. I am using one in my 68 Barracuda and have no plans what so ever to swap it out with anything else.