Hello everyone. I am looking for some help regarding front hub conversion. I have a '91 f150 4x4 with the OEM push button auto locking hubs. I have tried converting to Mile Marker manual hubs pt # 104 but have been having a lot of problems with axle movement and bearing issues. I have emailed mile marker and I am awaiting a response but was wondering if anyone has made this change and had the fitment problems that I am experiencing and how they were resolved. The fitment problem is as follows, the hub will not go all the way on with the axle retaining c-clip and spline washer in place. If you use a much thinner after market spline washer, but leave off axle retaining c-clip the hub will go on and you can use the accompanying outer lock ring and snap ring with significantly much less play in the axle, however, still small amount of play is present. Looking forward to hearing from someone, thanks.

 

Since you didn't explain exactly what "axle movement" you're seeing (the axles are all supposed to move) or "bearing issues" you have, no one can really help you with those. Post SEVERAL pics, each with detailed description.

The most common problem I've seen is that people don't realize they have to reach behind the steering knuckle & push the u-joint outboard to get the washers & C-rings in-place correctly. Post pics of how yours are assembled. But you only need 1 retaining ring on the axle splines; either the inboard C-ring (1B093) directly against the spline washers (3B458), OR the outboard ring installed after the hub lock. Not both. Does yours have the early 1-piece steel spline washer, or the later 3-piece as this diagram shows?

(click this text)


The rest of that photo album explains most of what you need to know about the brakes & hubs on these trucks.