Pinion leak just started

IDIDIDIhoDhoDhoDO

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So the truck in a 1988 F250 7.3 10.25 sterling, I noticed an oil stain on the ground today under the pinion of the truck's rear axle. It's a brand new leak. I took a video of the play in the pinion here.

I've read a little about this issue here and elsewhere and apparently the 1st generation 10.25 like this truck has has an issue where the pinion/yoke splines are not long enough and allow some wobble to develop which can not only cause leaks but also turn into pinion bearing damage and then finally pinion and differential damage.

I have never dug into a pinion before so I'm not too sure what to do here. One post from another user that had the same issue was recommended to pull the pinion nut, pull the yoke, pull the seal, pull the outer bearing and inspect the bearing. If the bearing and race look okay then reinstall with a new seal, retorque the nut while doing your best to preload the bearings properly, using the deadspace of the differential gearing backlash to try and feel for pinion bearing preload, then call it good.

Is that my best option? If you look at the wobble in the video does it look like I have more problems than just needing a new seal? Thanks.
 

u2slow

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I would get a solid pinion spacer in advance. No guesswork on tightening the nut. That lets you fully torque it to spec without further sleeve crushing.

Pre-loading used bearings isn't what you want to do.
 

IDIDIDIhoDhoDhoDO

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After getting the driveshaft off I was surprised that the yoke was actually loose on the pinion shaft. You could see where the yoke and the pinion nut had actually worn into each other a little bit because of the yoke being able to wobble. Anyway all is good now, I hope. Thanks 2slow.
 

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