what is it? putting in an arb with new 4.56 gears and all the instructions tell me to check somewhere else.

Dallas

I think it is 55lbs, but randy's ring and pinion has a list I think...

Go to Randy's (http://www.ring-pinion.com) and download the R&P install manual. Its a great manual, and the last page is all the specs for about any diff you can think of. And yeah, its 55.