Rear wheel bearings

[Plante]

We had our rear wheel bearings replaced a couple weeks ago and then went on a trip last week.  One of the bearings failed apparently because it wasn't getting enough grease from the differential.  The bearing 'froze', locked the rear wheel, and slid us to a stop.  Scary!!.  Because of what happened to us Les Schwab Tire Stores now packs the bearings with grease before installing.  It might be something to mention to your mechanic if you have bearing work.

[handyman]

Its been many years sence I'v taken apart the rear wheels on these rigs but if the old memery is still working these bearings dont get oil from the rear end they are packed bearings I might be wrong if not your mech owes you some money the only area that has oil is the axel shaft and it has it's own seal on the center cap  

[Plante]

I don't know if all years are the same but the bearings on my '78 gets the 90 weight grease from the differential.  Packing the bearings is more of a safety precaution in case the differential is low on oil.  If the oil level is correct the packed grease in the bearing will be washed away by the 90 weight oil anyway.

[Richard Peterson]

There is a modification to the differential which involves putting a plumbing elbow in the fill hole which allows you to top off the differential oil at a higher level.  This ensures that you have enough grease to keep the bearings lubricated.  This is discussed in a early journal, I forget which one.  I made this modification and found it was easiest when taking the back plate off the differential.    

[Conrad]

Differential oil in the rear bearing?  Uh-uh    .  I just did a brake and bearing job on my rig.  No differential oil should be present!  I have the Full floating rear axle, Spicer 60 from what the manuals tell me.  I removed the rear hubs and expected rear end oil to just flow out the axle shaft.  Not a drop.  Seems listening to all the other experts before I did this made me apprehensive.  I have heard the story of the rear end oil being used to lube the bearings but it always sounded questionalble.

What I did find is that bearing grease was still present in the bearings    .
I replaced both the races (cups) and bearings both outboard and inboard on both sides.  Since I was there I had the drums turned (before new races put in) and replaced the brake shoes, cylinders and brake spring hardware.  Those rear end hubs/drums are HEAVY!  I used high temp grease, same as for the front disc brakes.

I don't know when the last work was done on my rig but the rear shoes had worn very evenly.  I think they weren't adjusted properly.

[handyman]

Thats what i said if you have oil in the bearing you have trouble and if your bearing frooze up like I said Id get my money back and find a new mech hope you don't have any other problems  

[junebob]

Rear wheel bearings.In our Dodge Clippers,[I don't know about Chevs]    Ask yourself where the grease[90 weight oil], comes from when your rear seals start to leak.An all to common occurance in these rear ends.The street ell and plug added to the filler hole in the back of your diferentual definately raises the lube level assuring lubrication to the rear bearings. A note of caution. Make sure your pressure relief valve on top of the differenyual housing is not plugged.    If it is the pressure buidup can blow the lubricant past the seals, resulting in ruined seals ,oil soaked brake linings,frozen up bearings etc. The up side is , if you see grease on the inside ,and occasionally outside, of your rear wheels.Run ,don't walk -to the nearest shop you trust.Bob Chaney

[Conrad]

Jim, I agree with you.  JuneBob, I don't.  

Correct me if I am wrong...Bearings must be packed with grease before installation.  What purpose would a gear oil bath provide?  Front bearings are just packed.  Seems reasonable that the same would apply to the rear bearings as well.  To me, dis-similar lube products being used simultaneously defies logic.

I can see where the 90 wt rear-end lube can migrate to the drive shaft ends, but I can't imagine that the bearings are immersed in the 90wt.

My manual tells me that the differential lube level should be at the bottom of the filler hole.  It does not state the capacity to be used.  I have had other vehicles where the manuals specify 1/2 to 1 inch below the filler hole.  I have always thought that the bottom of the differential ring gear was immersed in the lube oil and picked it up thereby spreading the lube over the remaining differential parts.  The heavy 90wt oil pretty much staying in the differential housing.
 
Anyone else care to weigh in?

[cat]

The Dodge shop manual states "repack the rear wheel bearings every 36,000 miles."  Ask yourself "Why would the Dodge Engineering Dept. be so stupid as to mix lubricants."  When this deal of adding a street ell to obtain a higher capacity first came out in the 80's I disagreed.  I still disagree.  If in doubt, read the shop manual.

[Travis]

Dodge decided to save a little money on differential oil by lowering the fill hole by one pint without Spicer's blessing. If in doubt call Spicer/Dana yourself. Fill while one wheel is jacked off the ground. Packing the bearings is neccessary and vital to new bearing break in and insures long life.

[junebob]

Rear wheel bearings. I,ll ask again.    
If the rear end lube was not supposed to travel out to the bearings. Then please afford me a practical explanation. How does the differental lube leaking out of a bad seal travel,OUTSIDE OF THE BEARING.onto your brakes ,wheel etc, without passing through the bearing first?. :confused:The manual saying the bearings should be packed upon installation has nothing to do with the continued additional lube as needed from the rear end.OPIONS are opinions.    My opinion is that the incident of the grease and the 90 wt. oil mixing is not a mute point. This occurance would be minumal- Unless your seal were leaking.Bob Chaney

[handyman]

Ok Bob I'll try to tell this the way it is on our rigs they have full flooting axels when you look at the rear wheels there is a large hub in the middle with six bolts around it you take out the bolts and rap the cap and the cap and axel come out that is all that goes to the thired member, you can lower the rig down and drive it with the other axel turning because the wheel and bearings are still where they were, to get the drums off and get to the bearings you have to bend up the lockings tabs on the big nuts inside where the axel came out you unscrew the outer nut then the iner nut then the drum and bearings and greese seal comes out and then you can get to your brakes it's a royal pain in the rear end no pun intended the only way that rear end oil could get into the bearings and or brakes and thats if the grease seal was bad but normaly unless theres to much oil in the rear end you shouldent have but a very small amount if any that should be thereif anyone wants to find out what Im telling all they have to do is pull the center cap they sell the gaskets at Kragen then you can see the nuts I hope this helps I try to give the best info I can along with 35 years of being a mech  

[Conrad]

I guess we can all figure out which way each of us wants to go on this.  I am just gonna stick with the manual and no modifications.  My mechanic friend didn't seem to have a definitive answer other than, "Some do, some don't.  Read the manual."

[Richard Peterson]

My rear end and axle shop says the oil from the differential in a Spicer 70 which is what most of us have in the Dodge, comes from the differential and flows through a galley in the hub to the bearings.  The reason to pack the bearings upon re-assembly is to lubricate them until the oil reaches them.  In any case, it is a good idea to feel the hubs when you are driving to check for over heating and signs of failure coming.  

[Plante]

I brought this topic up just to warn everyone of a possible problem - sorry to cause such an uproar.  Although thats what makes this website so neat - the help and difference of opinion.  Here is an update:  By the time I got home from this trip I was feeling a vibration.  I thought it had something to do with the motor.  It turned out to be the race and bearing at the back of the tranny and the front 'U' joint on the drive shaft.  My mechanic feels this was caused by the wheel bearing locking up and wants me to get Les Schwab Tire Center to pay for the repair.