Quote: What do you mean by "split the sleeve"? I don't understand.
Its a 489 case, right... it uses a crush sleeve on the pinion... apply enough load and the pinion will push forwards and crush it more and thats the start of what you have... heavy cars WILL break a 8 3/4... I still use a 8 3/4 but my car is light... with a 1.19 60'