So I replaced all the front wheel bearings and seals 3 years ago, and the disc hubs too. Now I have this strange problem...the front driver wheel bearing gets some play in it top to bottom. I pull off the auto 4x4 components and tighten the spindle nut back up per spec, then replace the stopper pin that keeps the nut from backing off, then seal everything back up. 30 or so miles later it's got slack again. I redo the above procedure...30 or so miles later slack again! I've done this 7 times now thinking it's either going to stop or break. I also have seated the spindle nut hard while turning the wheel backwards and then backed off a quarter turn and torqued to spec which is just lightly snug for my year 1995 4x4 with Auto hubs. I'm also post 4/1995 so the parts and procedure I follow are listed for after that date or a 1996 is the same. I followed the same replacement on the passenger wheel, and the same torque procedure from the service manual and I've never had a problem with that wheel.

What do you think I should do?

 

You have just the one nut in there, right? If so then I'd try a new lock nut.

 

Yes just the one nut...but it's not backing out with that cotter pin thingy in there, right?

 

Oh I didn't know it had a cotter pin. It's been a while since I ripped out my auto hubs and replaced with manual ones so I don't remember exactly what they looked like. I wanna say mine had just a self-locking nut in there and no cotter pins.

If there's a cotter pin then no the nut can't move. Did you seat the new races all the way in when you replaced the bearings?

 

Yes there is a cotter pin contraption in there to keep it from backing out. Solely for that purpose too. I thought I seated everything but maybe not. I have cranked down the wheel nut pretty good now and backed off a bit and it's still doing it. I would have thought that would have seated everything if I hadn't before when installing the new races and bearings. If I remember right, the races I didn't use because the new hubs already had them pressed in. I guess I'll keep doing this procedure since the wheel nut is slowly moving in...somethings either got to seat finally, or bust!

 

Since I've only worked on 94 is an older of this series truck I don't know what that cotter pin thingy locking nut looks like but going from what I know from the older trucks there's three possibilities, The locking nut isn't actually locking and letting it loosen, The bearings are going out and ready to grenade or The bearing races were not installed all the way in initially but very unlikely to be the problem now after three years.
I'm guessing the lock nut isn't locking.

 

I know for a fact the wheel nut isn't backing off because the cotter pin stays put keeping it from doing so.

Could it be a spun bearing race in the Hub? I've never had that before so not sure what those symptoms would be, but I came across some posts about it where a bearing kept getting loose. Would that give you play in the bearings without loosening the wheel nut at all?

 

More research done and here's some more info...the nut I'm referring to is the spindle nut and it tightens the hub which loads the bearings. Dixie--I picked up on one of your posts about deep water...I drove through bumper deep water a year ago and that's when I started having this problem. Since repeating tightening wasn't working, 2 months ago I tore it all apart and noticed I have scoring on the spindle, but not where the bearings ride. Is this ok? Perhaps a shop did that when they rebuilt my front end a few years back. I mean there are some gouges. I could file them down but again no bearing is touching them. Besides don't the bearings roll within and on races in the hub? When I inspected the inner, outer bearings and races they were good (no wear or discoloration) and seals seamed ok. Grease was almost hard and crusty! Must of gotten hot. Or wet? I repacked them and regreased everything. No noise except after 30 miles when I get the sound of a loose or bad bearing and notice the play in the hub again, retighten, sound goes away.

Thinking about starting over with new inner/outer bearings, seals, and pulling the races out of the hubs (they came already installed in the new one-piece brake disc/hub assembly when I bought it 3 years ago). What a pain. I'll have to rent a tool to get those races out I suppose.

Any final thoughts before I tear into this again? Do I need a new spindle too?

 

Your new grease got all hard and crusty? I can't think of any reason for that.

The reason you want to service your bearings after they go for a swim is because the grease will absorb water which ruins it's lubrication ability. Rust can also start when there's enough water present.

If this were my truck I would pull the hubs and make damn sure the races are seated all the way down. Are you sure your torque wrench is accurate? I converted my hubs to manual lockout so I haven't ever seen the specs for the autos, but for what it's worth the procedure for manual hubs is to tighten the spindle but to 50 ft-lbs while spinning the hub, then back off 1/4 turn. On the manual hubs you would then put in the locking ring and outer nut (lock nut) which gets torqued to 150 ft-lbs but that part don't apply to you since you only have a spindle nut.

There are only so many places in there for play to develop. Either the races ain't seated all the way down, the bearings or races are wearing fast, or the spindle nut is coming loose. We already verified the spindle nut stays tight and the bearings/races are okay, I can't think of anything else, besides races not being seated, other than maybe your wrench is out of calibration and you ain't tightening the nut tight enough to begin with.

Don't worry about any rough spots if they're away from the bearings.

 

Thanks everyone! I'll tear it apart to look at the races tomorrow.

 

Been down this path before. The inner race had spun in the hub. I replaced the complete hub and bearings and haven't had an issue in the seven or so years since.

 

Thanks White. When I get the hub off, what do I look for to confirm it spun? Is it a defect usually or did I tighten too much and caused it? My disc and hub are one assembly, kinda expensive. Just want to be sure.

 

In my case, when I pulled the hub assembly, the race was physically loose. From what I was able to surmise the PO had used regular wheel bearing grease rather than "disc brake rated" wheel bearing grease when repacking these bearings just prior to my purchase.

 

Ok. Update... I definitely spun the outer bearing race. It was VERY loose in every direction and had worn the backside hub lip down that the race seats against. So a new hub is on the way with new bearings and a wheel hub grease seal. My findings for cause are two possibilities. Defective hub allowed race to come loose (or it was loose from the beginning, I never checked it for tightness when I installed it) or I over tightened the spindle nut at some point therefore crushing the race into the hub and deforming the Chinese hunk of junk.

I'll check the new hub for sure and also be careful on tightening the spindle nut. I only have the one axel nut that loads the two bearings so I don't think I need to seat them hard, right? Just snug it up a bit and back off the nut a quarter turn, then just tight enough where there's no play top to bottom? Unsure why there is a seating procedure when the races come already pressed into the hub, and the bearings just ride on top of the races, so what are you supposed to be seating??

Is my Lucas red tacky grease fine? others on the bronco forum suggested grease only on the bearings and ATF on hub, spindle, splines and 4wd components. Is that what you recommend?

 

Glad you were able to find clear-cut evidence. If the Lucas grease is rated for disc brake wheel bearings, then it should be fine. I just pack the bearings; I don't apply anything to the other parts you mentioned.