My big case has slop in its pinion but is otherwise just fine. It's a low mile unit, the seals/bearings are just fine and there's no reason to rebuild it.
Do I need to start from scratch and put a new crush unit in there or can it simply be tightened until the slop's out of it?
Bill in MN wrote:Axial. It's not much but enough to translate to a few inches when the wheels are rotated.
That sounds normal to me. There is a specific amount of lash built into a ring & pinion set up. If your pinion isn't sliding in and out of the front of the diff (pinion depth) or wobbling from side to side, it should be fine.
The best way to judge the health of a diff is to inspect the wear patterns on the pinion and ring gear teeth.
I can see no wear in either the ring or pinion. It's loose enough to clank when I engage the trans, however, and translates to about 1/8" inch slop in the drive shaft.
It may in fact be normal. I have 0 sound insulation in the car, the tunnel's made of core and kevlar so every driveline noise resonates like crazy. It is not a quiet environment.
I'm not sure what the lash is supposed to be for that diff, but I've typically seen it between .008 and .012 or so. You could pull the diff cover and measure it if you're concerned. You could also take pictures of the ring gear and post what the tooth wear pattern looks like.
Here is an example of what the wear pattern should look like and what it can look like if there is a problem:
That looks ok to me, but it's difficult to see if the wear pattern has changed. It might be worth it to paint up the teeth to see what the wear pattern is now. They make a special paint for it.
It's tough to see in the flash but looking at it in good light it's not worth messing with. There are no abnormal wear patterns. I kinda doubt it's going to break.
