Help me troubleshoot a vibration

[M1Gunner]

I would definitely install new u-joint(s) before going any farther.

The slight rotational play is just the backlash with your ring and pinion gears. If there no play up/down left/right then the pinion bearing clearances are still good.

 

[aces-n-eights]

Good deal, that's what I will do.

Thanks

 

[Floep]

Spline , U joint into rear of transfer case dry. Easy to lube by taking driveshaft out and put some never seize on spline. If clunk gone, there are different permanent fixes, depending on the mechanics opinion. While you got the D.S. out re place the pinion seal, easy job but read up exactly how, since you might not get the pre load on the pinion right, if done improperly.

 

[aces-n-eights]

Good suggestion, thanks!

 

[Tacky]

I would not put antiseize on the spline, it will get into the transfer case oil. the spline should be lubricated by the t-case fluid. If fluid is aged it may cause a stop clunk, but should not cause a vibration.
II was pretty sure you had a u-joint or other driveshaft issue at your first post.

 

[aces-n-eights]

Just to follow up... i replaced both u-joints and the pinion seal. All good, the vibration is gone.