Pinnon Shaft/Yoke Issues

[cajuncannon03]

68 F-100, 325 Rear End, after restoration,slack in pinnon shaft, did not address, happy to drive it. After a few months and 650 miles, leak developed at yoke seal. Took apart, lots of play in bearings, replaced both bearings and race, after tightening everything, still have slack in pinnon shaft. Nut is completely tight and will not tighten any more. I think on restoration I may have misplace a spacer or washer behind yoke to contact front bearing, I have nothing, diagram shows something there. Can anyone provide input. Does anyone have complete pinnon shaft and yoke assy. with all components willing to sell? Any input would be appreciated. Ford 9" 10 bolt rear end.

[ultraranger]

If the 3rd member was disassembled and the parts were not put back together in the correct order, or in the correct order but with incorrect tolerances, then the damage has already been done.

You cannot simply swap the driving pinion/pinion housing out for another one. Gears are lapped in matched sets. Taking a driving pinion from one gear set and putting it with a ring gear from another gear set (or vise-versa) will only work for a very short time before they are no longer a working gear set.

You will have to have the 3rd member rebuilt with new bearings & gears or swap out the entire 3rd member assembly, for another, to remedy this problem.

[68 Ford Stepside]

I really don't know how you drove as far as you did. You can't just throw everything together, tighten it as tight as you can & go. There are solid precision spacers used in some & collapsible spacers used in others. The drive pinion nut has a specific torque figure that must be used. Once the pinion is built & installed shims are used to set pinion depth & to set the pinion gear pattern to the ring gear. The procedures have to be followed closely or you can destroy a new set of bearings before you ever get to use them. Normally, you'll have to buy several spacers to end up with the proper end play by changing them out. Considering the cost of the bearing pullers & installation tools needed, you may want to consider having it built by a professional mechanic. It's your call.