Very Bad Vibration

[s1ngletracker]

The marking compound is called "Prussian Blue" and I bought it at Napa.

The cursory check of a poorly shimmed rear diff is grabbing the flange (like you said) and seeing how much rotation you get before your axles start to turn. The factory service manual has a spec on it, I believe it is like 5mm.

It isn't really smart to use a bearing with a different race, as they wear together, but I doubt that alone was the problem, again, talking about 5mph.

I've rebuilt a DSM rear diff (the correct way) and I actually have the special tools for it and know how to use them, unlike 99.7% of dsm folks. You can PM me with questions if you want.

[b00sted_spyder]

That spacer is a shim. It is a good idea to swap it over to the new pinion so you can get a start on your gear pattern. Then after you see what pattern you have, you can adjust the shim to get a good pattern. If you didn't swap anything over, I can guarantee you that your pattern is off. I'm willing to bet the backlash is way off.

[mark4g63t]

So should I or should I not swap that bearing/shim? I will check the rotational measurement in the morning. Thanks for the help so far guys!

[b00sted_spyder]

If it was me, I would check the pattern first. If you didn't put that shim on the new pinion, your pinion to gear ring contact must be way off unless the new one came with a shim as well. Did you use a new crush sleeve when you reassembled it?

[s1ngletracker]

checking the play in the rear end is way easier, and I believe that is the first step the FSM recommends.

[dsmghost]

If you changed ring and pinion gears, you have to check contact pattern.

[mark4g63t]

If it was me, I would check the pattern first. If you didn't put that shim on the new pinion, your pinion to gear ring contact must be way off unless the new one came with a shim as well. Did you use a new crush sleeve when you reassembled it?

I believe it came with a shim but I'm not 100% sure because I didn't swap any of that over. I will take the diff out tomorrow. I did not use a new crush sleeve but am now seeing they are non-reusable.

[b00sted_spyder]

I'm willing to bet the vibration at 5mph is from the rear diff. It wasn't setup correctly. Get the right pattern and fix that rear camber asap. The driveshaft would give you a vibration at higher speed unless the hanger bearing rubber ripped right off but the low vibration is probably coming from the rear diff.

[s1ngletracker]

DSM Diffs do not have crush sleeves.

[mark4g63t]

Good to know. I've read a couple threads on getting the correct pattern. Some mention to measure backlash before painting the teeth and doing the pattern test. Any thoughts on that?
I'm going to remove the diff today and take a look.