whats up everyone. well its time to change my posi unit out. the stock unit is starting to go south.. when i look at the different units available i am not sure if i have a 26 or 28 spline. see when i run the numbers from my car it says i should have a 9 inch borg warner underneath of her but i have a 10 bolt.. the car has been in storage the last few years and the last thing i really did was change to 3.73 gears. and there is no rear end tag on the cover.. so how can i tell in short of tearing it apart?? are there any other id numbers on the rear end anywhere that if i post you guys could tell me what unit to order? what is the best unit out there? thanks again for the help

 

there should be some numbers on the left hand side of ur diff.The numbers should contain the yr of ur rear if its 90 or above its 28 if its under 90 its prolly 26.Im new to this but thats what i gathered so far im sure someone will correct me if im wrong.

 

89 was a transition year. if your car is an '89, you might have 26 or 28 splines. if it's 87 or older, it has 26 splines. if it is a 90 or newer, it has 28 splines. thats as long as you have a 10 bolt.