First of all, the 9" is NOT lighter. In order to gain equal strength, the 9" and D60 are equal in weight.

There are options all the way down to 3.08 gears for the D60. If you need taller than 3.08 gears you need an over drive, because you have compromised low (1st) gear.

I have no idea why you think ride height is compromised by pinion height.

It takes me the same time to set up a D60 as it does a 9". I'm sure anyone who has done them would agree.

It is the same money to set up either diff. The 9" is FAR more expensive than the D60.

I would have to look up pinion diameters but I've never broken a D60 pinion.
The D60 takes LESS HP to drive with LOWER gears (higher numerically) than the 9". This is NOT linear. As you go to lower gears the 9" starts to eat power like mad. The push is 3.90. At that ratio, they both take the same power to turn. By the time you get to 4.56, the 9" is wasting power. For years I ran 5.57 gears in my drag car. The gentleman who taught me how to set up diffs told me, in his personal testing, at that ratio, the 9" was eating 35-40 HP. And he actually tested them. That's why I used the D60. It was cheaper, just as strong, and took less HP to drive.


As for ease of replacement, that is the biggest bag of bullcrap I have ever heard. I can't hardly get a racer to pull all 8 spark plugs, let alone drop a 3rd member to change gears. And what about cost? You want me to think guys that [censored] about the cost of synthetic oils are going to front for 2 9" 3rd members? A Comp guy probably. A fast bracket guy maybe. But the rest of us? Fat chance.


In the end, I really don't care what diff anyone uses in their car. It's their stuff and their money. But what eats my draws is the general lack of knowledge about this stuff out there. It's sad that for DECADES the same crap has been passed around as truth.


And if Dr. Diff sees this, I would love his input and thoughts.