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Symptoms of too-tight backlash???


NAXJA Forum User
Jing Zhou, China
Well, I got my rear end in this evening. After I set the gears up and got a good pattern, I pressed the final bearings on and put it all together. I checked the pattern a few more times just to be safe and it seemed the more I played with it, the more my backlash tightened up. I decided it was the marking compound just gunking up and making everything tighter. I took it for the first drive tonight and I had no noise when on the throttle, but pretty bad gear noise when coasting... cut the test drive really short. I thought I heard once that backlash to tight would cause a symptom like that... is that true?? Just want to know where to start when I open it all up tomorrow.

Set up ...

If you have done correct pattern on both sides (drive and coast), there should have not been any noise. However, till gears arent broken in (500miles) you might get a little noise. Meke sure u let diff cooll down after first test drive and do not go for a highway ride till. After first d-drive, I would drain oil and re-check patterns and adj as needed...But like I said if pattern is good, there should not be any further adj needed....
Just check it carefully ....
Ummm... ya, I ran a pattern and it was weird, not like anything I've seen in any manuals or anything. It was also to hard to turn the gears backwards, even with crowbar leverage on the wheel lugs. I went to take the driveshaft off to start tearing into everything and found lots of play in the axle yoke. Some crook broke into my garage last night and loosened the pinion nut (...or maybe some idiot forgot to tighten it after the final assembly :anon: ). So, I tightened it up, ran a great pattern and had a great test drive. Just FYI. I also heard that worn pinion bearings will have the same effects, gear noise on deceleration.

Marcus 'make sure you tighten it all up!!!' Riley
gears shouldn't make ANY noise no matter what.....

sounds like a bearing wasn't seated properly, or you may have torn a shim.

I'd pull it apart and inspect....

if you can, take some pics of the pattern, and I can tell you whats going on.

what was the backlash anyway?
The final setting before I forgot to tighten the pinion back up (see above post) and it deflected and made everything wacky was .004". I went a little tighter because the ARB says to, but mostly because you guys have all talked about how it will open itself up as I drive and put some miles on them. Got the slop out of the pinion and all is grand now.