How do you know 8 3/4 is bad?

[sublimeswinger]

Im going to be picking up a 8 3/4 rear end for my 72 dart.How do i know if its good or not?Is there a test or something? :sad2:

 

[fishy68]

Well there's really no foolproof test because you can't put it under a load. All you can do is spin it over by hand and feel the bearings to see if there is any rough spots on them and if it feels like it spins over smoothly. Also feel the backlash in the pinion. If you can slop the yoke back and forth alot (like a 1/4 inch or more) then the gears are worn alot. If it's a sure-grip you really need 2 guys, one on each end with 2 foot pry bars to stick in the wheel studs and turn them opposite directions to see how tight (or sloppy) the sure-grip unit is. It should be pretty hard to turn opposite directions. Also pull the brake drums and have a look at the brakes. That is about all you can do to check one out. LOL