I have a 12 bolt with a 2.73 gear ratio and I would like to change the gear to a 3.42 or 3.31. But My question is, does anybody make a ring and pinion that fits a series 2 carrier? I know that they have to be a special gear to fit. Thanks

Nope. The 7.5 has some 3 series gears that will fit the 2 series differential, but it's the only one. The only way to use 3 series gears in the 12 bolt with a 2 series differential is with a spacer. I do not recommend using a spacer.

I had the same question, why not the spacer? So there is no other way?

I had the same question, why not the spacer? So there is no other way?
Buy a three series carrier IMO you can use a spacer as long as you are
Not planning on using slicks although I have done that with a three and
Spacer to the 4s

Ok thanks, was trying to stay budget minded by keeping the same carrier. Oh well. They make thicker gears, but not in the ratio I was looking for. I also heard bad things about spacers.

http://thumb7.webshots.net/t/14/15/8/46/32/2501846320041712107dAvBiX_th.jpg (http://rides.webshots.com/photo/2501846320041712107dAvBiX)
Here is just one example of why not to use a spacer. I've seen this several times. Notice all of the broken bolts in the bottom of the housing and the gap behind the ring gear. This is a street car. I have other examples of why not to use a spacer.

BGH,
awesome pic.

tom