REAR BEARING LUBRICATION

[RICH MUISE]

OK, My ignorance is prevailing again. I never gave rear bearings much thought in the past. I just had it in the back of my head they were grease packed like front bearings, but looking at my axels that I had altered, I realized the bearings were not grease packed. Now, finally actually giving it some thought, I realized the bearings are probably just lubricated with the differential oil/fluid from the center section, so grease packing would be futile because the oil would just disolve the grease anyway. I'm also assuming that the oil is slung to the outer ends by the movement of the gears/axles. Am I correct, and should the bearings be pretreated with something like stp on initial assembly?

[oldave57]

The outer rear axle bearings are sealed ball bearings (permanently lubed type) that require no additional lubrication.  The rear axle seals are actually inboard of the bearing so the differential lube doesn't reach the bearing.  It does seem like there should be some way to lube the bearings, but the sealed ball bearings seem to last very well without lube.

Regards,
Dave

[hiball3985]

How did you determine the bearings weren't greased packed? They should be a sealed bearing.

[RICH MUISE]

After Dave's post, I went out and looked at my old axle, because what he was telling me wasn't matching up to my new axles. My oem's are the sealed bearing type. My new ones are open tapered,and the seal is outboard of the bearing.

[oldave57]

Rich,

Do you have an aftermarket axle housing with the axle set-up you show in the photo?  I don't see how the seal could have room to the outside of the bearing with the original axle housing.  Now I see why you were questioning the lube to the bearings because with the axle bearing and seal set-up your photos are showing, it does appear that the lube could come from the center differential housing to the roller bearing that is shown since the seal is to the outboard side of the bearing.

Dave

[hiball3985]

That interesting, with that set up I can only guess that the bearing retainer is a U shape?

[Ford Blue blood]

Is there a bearing race in the housing end?

[RICH MUISE]

Dave...yes,aftermarket ends. I had the case narrowed and converted to big bearing/old style bolt pattern.
Bill...yes, there is a cone/tapered race in the new ends.
Jim...Yes, the bearing retainer is open..goes on after the axle is in. same with the brackets in the disc brake kit.

[hiball3985]

Nice set up Rich

[RICH MUISE]

So, my assertion that the bearing lubrication is from the differential gear oil is correct, then? I've got everything on the driver's side cleaned up and ready to go back together...I think I'll pick up some stp or assembly lube for the bearings just for a little insurance.

[Lgcustom]

With that open bearing setup, be sure you don't install the seals inside the housing tubes or they'll block the lube getting out to the ends.

[gasman826]

Small bearing and Early Big Bearing are sealed, ball bearings and use a separate seal...use no lubrication from the center section.  Late Big Bearings are an intergrated, single unit, seal and tapered bearing.  LBB are sold as one unit.  I thought you had the housing modified for EBB?  My experience is that once the Late bearing is split, it will have a tendency to leak.  I think they are too expensive to replace every time you split the race from the tapered bearing.

[RICH MUISE]

I check-fit the axle to make sure the bearing was still seating after the remachining (it was), but I didn't even try to slide the seal into position. I'm assuming at this point the seal fits into the groove on the face. I don't think I could even get it into the axle tube if I tried, but thanks for the heads up. Colby told me to make sure I check fit the seating in case material had to be removed from the spline end to compensate for the .140 the bearing shoulder was moved out, although he didn't think it would.
That's definetly one nice thing about the tapered bearing...you can see where the rollers are  making contact. I've never assembled the oem style with the sealed bearing, but I'm guessing it would be hard to tell if it's bottoming on the bearing or interference at the axle end.

[RICH MUISE]

Gary...I guess all I know is the bolt pattern is old style/EBB, so I'm not sure what I've got here...maybe a combination of the two, but it also didn't seem like the seal was an integral part of the bearing. I guess I'll figure out what it is I have before too long. right now, after what you said, I'm thinking he bought a late end and drilled it for the ebb pattern??
edit...ok nap is over. What you're telling me about the bearing style corresponding to LBB would go along with the 2.5 offset I had (which is a LBB offset), and why I had to have him remachine the axle to bring it to the 2.36 old style offset.

[gasman826]

Big Bearings are the same size.  ID and OD of the bearing is the same.  The big bearing ends are different.  The flange bolt pattern is different.  The Early Big Bearing was a sealed ball bearing that uses a drive-in seal (looks much like a front wheel bearing seal) to keep the oil from running out.  Prep the seal with a little lube for startup and a little grease on the outside of the bearing so it doesn't rust into the new flange.  The Late Big Bearing (like the one in your picture) is one piece tapered roller bearing that seals on the outer side of the bearing and is lubed by the internal gear lube.  In your picture, the race that is in the axle housing should be on the tapered bearing.  No prep is necessary except for a little lube on the outside of the bearing to help keep it from rusting into the new bearing end.  New bearings come out of the package with startup lube.  You should not split the race from the bearing.  The likelihood of leakage will increase.  Since your are already committed to putting a Late Big Bearing into a Early Big Bearing Axle End, I would go ahead with what you have. 

As far as testing the axle 'bottoming out', Ford Traction Loc and open center sections have pinion pins.  If the axle is too long, the axle will bottom out into the pinion pin.  This is NOT a good thing.  You've test fitted before with modeling clay,  put a dab of grease on the end of your axle.  Insert it and tighten the axle flange nuts (with the disc brake support if that is the way it is finish installed).  Check to see if the nuts draw the bearing keeper plate tight to the new axle end.  Rotate the axle, if it binds, the axle is too long.  Remove the axle and check the modeling clay (dab of grease).  If the dab of grease indicates there is no clearance, the axle is too long.  NOTE:  Detroit Lockers have no pinion pin so axles can be longer.  If the axle is too long, cut it off with a cut-off wheel.  Grind a little chamfer to help the axle slide into the side gears.  Retest fit for clearance.