5 ton rear axle seal fix procedure

[M.WARREN]

5 ton bearing numbers

Hello all, new to steel soliers here. I have to say this looks like a killer site with a lot of help.I have a question on the 5 tons .I need to replace the inner and outer bearings does anyone have the timkin or the national numbers on them?

 

[crasheej]

Have you pulled the axle apart wet ? If so you will find a number on the old bearings take the old ones to the part store they will cross them take your green stamps and you go home put the new seals that you got when you you took them with your old bearings And your good to go.Try it it might work that way.

 

[jimk]

Thanks jpekarek. Some other suggestions:

Use the correct tool for the bearing nuts : 250-400ft*lbs

Always replace oil soaked linings. They will bleed oil when the get hot. My local brake shop got linings for $66/axle and $6/shoe to install them.

Check the adapter to hub bolts, even if they are safety wired. Mine were loose - 81-104 lb-ft

Have the inner seal on hub -before- you install or disturb the adapter. It will align the two. If you don't you can get a non concentric drum because there is substantial side slop in the bolt/bolt holes. A 6" water pipe a few " long can be made into a seal driver with a little grinding.

Take the adapter off the drum, clean the oily crude/muck behind it, clean the 8(?) adapter drain holes and put deflector on with some sealer behind it.

Front spindle nuts are 130-167 lb-ft, sealer behind deflector. Drain slot faces down, align w/drain hole in knuckle

Check for bad wheel stud threads. They are easy to replace now and only cost 3-4$ each.

Wipe some grease inside hub for corrosion protection. Don't fill hub.

Clean the rust prevention coating out of shoe pivot holes if shoes got dipped when relining.

Check wheel cyl boots for holes. The will probably be swollen if oily. They are available new for 2 or 3$.

Pull the lower shoe pins out of backing plate, wire wheel and grease them. The 2 flats don't allow for much torque. If the are stuck you'll be glad you did later. If you are relining shoes you will need to turn them to get the drum on, and then to do the major. New linings may not conform well enough to correctly feeler gauge both the top (.010) and bottom (.020) at same time. Set bottoms. The tops may be way to wide when drums just stop dragging. Plan to redo them after a 100/1000 miles. You will be able to get them closer to .010 after they wear in. NOS shoes are expensive. The cast ones and may fit linings better (at first).

Do the major even if you reuse shoes.

New grade 8 1/4x28 Stover lock nuts (for the shoe hold downs) will wreck the threads. Better to reuse the old ones.

Jack stands.

 

[Krink545]

A BIG Thank You to jpekarek for taking the time to document it all.
I've done hubs on My GMC Topkick before but its always good to see some pics so you know what your getting into. The hubs on a M923 must be a lot bigger because there is no way you could pick them to put back on the axle.

Now a question. I noticed you just snugged up the bearing nut to just take out the play. In the TM for the M939 series(I have a M923) it says to tighten nut to 50Lbs while turning hub. Then back off 1/6 to 1/4 turn to line up lock pin. Torque lock nut to 250-300Lbs. Is it different for a M54 series than a M939 series? I hope that the TM is correct because I finished one hub last night.

 

[sidel2426]

I recently change the seals and wear rings on a M817 and I thought I would include some pictures of how I installed the seals and wear rings.

When I took the hubs off I noticed that the wear rings were not positioned all the way back to the step on the axle. This bothered me because there was no way to know how far to install the new wear rings on the axle. After I thought about it for a while I realized the inner bearing and installation of the hub is what sets the proper distance for the wear ring on the axle.

I installed the inner bearing in the hub. Next I installed the seal in the hub. I then placed the wear ring inside the seal (refer to picture below). When I placed the hub on the axle I installed the outer bearing and hub nut. I finger tightened the hub nut which centered up the hub on the axle. Now tightening up the hub nut with a socket and wrench will cause the inner bearing to push the wear ring onto the axle shaft the proper distance it needs to be. Once the hub nut has been tightened until it stops you can back off the nut and then follow the proper procedure for setting the bearing preload. For those that don't have a jack or something to hold up the hub while installing it on the axle this wear ring will also protect the seal from being damaged by the threads on the axle.

I hope this helps

 

[73m819]

1 - I am confoosed... as usual. I have never done a 5-ton axle, so this is purely a question and not a second guess. Anyway, on all the full floater axles I have done, there is only one inner seal at the back of the hub, and the hub's bearings are lubricated with gear oil. But on this thing you have that outer seal and are packing the bearings with grease. So I guess my question is does the gear oil lubricate the hub bearings at all, or are they completely dependent on the grease you repacked them in? One would think the outer seal is a bad thing since gear oil would be a much better lubricant, and the flange gasket should keep everything in the axle.

2 - Tony, Heavy axles dont lubricate quite like car axles. More like the front on a rear drive car. You MUST pack those bearings well, with a quality qrease. Your Lube Order(LO-9-2320-260-12) calls for GAA which is Grease, Automotive and Artillery(MI1-G-10924) which is Castrol 610, NGLI #2 Grease. Hope this Helps

1 - The MILITARY is who speced the outer seal and GREASE hubs, this was to keep water from getting into the rear chunk area for amphibious operations, the 5t axles ARE wet hub and were used by the civi world for medium to heavy use (cranes, gradealls, drills, ect.) for many years.
You can go back to wet hubs, to do so install NEW ware rings, NEW axle/hub seals, NOT NOS (they tend to be dry and not as flexible), once you change back to wet hubs, you WILL find the the rear hubs WILL run at least 20 deg. COOLER, the reason for this is grease will hold the heat while the hub, and axle housing, act as a heat sink, sucking out the heat from the oil.

Before any of you "experts" call the above BS, take a look in some OLD "Motor Truck Repair Manuals" like #10, this is where I got all the rear ratios, these manuals go into the repair/rebuilding of these axles, also we put this to the test when we RESTORED the restored m62.

2 - This IS 110% FALSE, 99.9% of heavy civi trucks ARE wet hub, The LO calls for grease because of amphibious operations, NOT for the well being of the bearing in everyday operation, as stated above the bearings run hotter in a grease hub. About ALL the NEW front wheel drive trucks (except most military trucks) ARE wet hub also, even some MVs are.

When doing a R/R of a rear wet hub, you pack the hub bearings lightly just so the bearing is lubed till the hub fills with oil. The proper filling sequence for filling a wet hub rear, is to bring the oil level up to the fill plug, take the truck out and do some figure 8s (this fills the hub), bring the truck back and top off the oil level, on front wheel drive wet hubs, there is a hub port like some trailers have that you fill through.

 

[Tow4]

What 73m819 said. I pulled one of the front tandem hubs on my m929 to repair a brake issue. The hub was full of gear oil and I put it back together that way. I left the outer seal in (it was shot anyway) because I wanted a washer between the bearing and nut. I didn't install a seal in the keyway. Next time I will either leave the seal out or notch the seal so the oil can flow more freely.

 

[Floridianson]

Respectely disagree with the oil thing and not filling hubs with grease. Our rears oil plug is not set high enough for oil bath bearings in my .02. and I will keep grease in there. Second I allways place a good amount of grease in the hub. This light coat of grease on the bearing and nothing in the hub is wrong in my .02!
In my .02 grease would be a better choise for a truck that might see fording. If there was a large amount off water to enter the hub the oil will float the oil right off the bearings. The grease would not in my .02.

 

[Floridianson]

Excellent step-by-step. You should produce a line of MV maintenance books.

If I saw anyone working for me use a chisel to remove or install a wheel bearing nut they would be fired. There is a right tool for everything. Sorry sad but true.

 

[infidel got me]

I use my engine hoist under my singles[the same way as in post #34]
If you have access to soldier 2,use him or her,these tire assy. are heavy.
I also agree with floridianson,use the right tool for the job.

 

[Tow4]

Since I have taken 2.5 ton and 5 ton hubs apart and found they were full of oil (and running very cool by the way), I don't really think the axle oil level needs to be any higher than is it is. If you think about it, the ring gear is churning the oil up and it will flow out to the hubs. Also consider it doesn't take much oil in the hubs to lube the bearings. How much oil is in a civi tractor steer axle or trailer hub with oil bath bearings? a quart or two? They have no heat or lube problems.

I'm going to go out on a limb and say that oil bath bearings are a lot better than greased (at least in heavy trucks) and that's why they are widely used. Works for me. YMMV

 

[Floridianson]

[QUOTE=73m819
Before any of you "experts" call the above BS,
2 - This IS 110% FALSE, 99.9% of heavy civi trucks ARE wet hub,

I am no expert Ron but I found the fill plug on anything that had oil bath bearings is much higher than the ones on our military rears. The oil bath has half the axle tube filled at all times. Look at ours it is not even to the bottom of the axle tube.Yes the axle will walk it out there but that's not good enough for me. To each his own truck but I trust a good grease packing and the correct way not to over tighten the first bearing nut to keep the bearings running right temps.

 

[dawico]

What a great thread. Thank you. I will be checking mine soon and the pics really help.

 

[73m819]

These 5t axles are stock axles that were used in the cicv world, all the later trucks that I have worked on seem to have the fill plug just at or a hair above the bottom of the tube, the proper way to fill a axle after a repair is to first, on the hub install lightly grease bearings so they are not dry (the warm oil will wash it away), second, fill the rear to the fill plug, third, take truck for test drive (checking on proper operation and this will fill the hubs, forth, top of rear.

It does NOT take a lot of oil to lube a rear, it is not a oil bath nor a totally immersed rear though some EXTREAM LOADED rears are but here is not the case, in fact TO MUCH oil in a rear WILL cause it to run warmer then it should because the oil cannot get rid of the heat because of to much metal is in contact with the hot oil, there has to be enough metal to draw the heat away from the contract area to keep the rear within op. temp.

There is NOTHING in my cicv books that talk about grease REAR hubs.

 

[infidel got me]

Thanks jpekarek. Some other suggestions:

Use the correct tool for the bearing nuts : 250-400ft*lbs

Always replace oil soaked linings. They will bleed oil when the get hot. My local brake shop got linings for $66/axle and $6/shoe to install them.

Check the adapter to hub bolts, even if they are safety wired. Mine were loose - 81-104 lb-ft

Have the inner seal on hub -before- you install or disturb the adapter. It will align the two. If you don't you can get a non concentric drum because there is substantial side slop in the bolt/bolt holes. A 6" water pipe a few " long can be made into a seal driver with a little grinding.

Take the adapter off the drum, clean the oily crude/muck behind it, clean the 8(?) adapter drain holes and put deflector on with some sealer behind it.

Front spindle nuts are 130-167 lb-ft, sealer behind deflector. Drain slot faces down, align w/drain hole in knuckle

Check for bad wheel stud threads. They are easy to replace now and only cost 3-4$ each.

Wipe some grease inside hub for corrosion protection. Don't fill hub.

Clean the rust prevention coating out of shoe pivot holes if shoes got dipped when relining.

Check wheel cyl boots for holes. The will probably be swollen if oily. They are available new for 2 or 3$.

Pull the lower shoe pins out of backing plate, wire wheel and grease them. The 2 flats don't allow for much torque. If the are stuck you'll be glad you did later. If you are relining shoes you will need to turn them to get the drum on, and then to do the major. New linings may not conform well enough to correctly feeler gauge both the top (.010) and bottom (.020) at same time. Set bottoms. The tops may be way to wide when drums just stop dragging. Plan to redo them after a 100/1000 miles. You will be able to get them closer to .010 after they wear in. NOS shoes are expensive. The cast ones and may fit linings better (at first).

Do the major even if you reuse shoes.

New grade 8 1/4x28 Stover lock nuts (for the shoe hold downs) will wreck the threads. Better to reuse the old ones.

Jack stands.

What bearing nut are we tourqing to 250 -400 ft.#

 

[Floridianson]

Not the first one to the bearing that's for shure. Jam nut yes. I like to take retaining nut down to 100/150 while spinning hub then back off half turn and with TQ wrench up to 50ft.lbs. Then put on the locking ring and see where the hole lines up. If it don't line up real close flip the locking ring over and check how close the hole is to lineing up. Pick the best side and I like to back off rather than tighten to make hole line up so pick the best side that does not back off the TQ as much but close to 1/4 turn looser.

Ron when I did my cicv trucks I used a wheel dolly and added most of the oil too the hub before install. Then when all axles are done and Diff. is toped off I just park the truck sideways on a grade for 15 mins. then reverse for 15 and then level park then top off Diff again.

Once again your trucks do what you think is right.

 

[Floridianson]

Not looking too argue but here is ours and here is the truck oil floating Diff. The true float bearing axle has almost half the axle tube filled with oil . Ours Just makes the bottom of the tube. Just saying and we still have to run grease in the front axle. I will allways stick with the grease.

 

[Floridianson]

[QUOTE=Tow4; How much oil is in a civi tractor steer axle or trailer hub with oil bath bearing?

Almost half way up the spindle.

 

[infidel got me]

Not the first one to the bearing that's for shure. Jam nut yes. I like to take retaining nut down to 100/150 while spinning hub then back off half turn and with TQ wrench up to 50ft.lbs. Then put on the locking ring and see where the hole lines up. If it don't line up real close flip the locking ring over and check how close the hole is to lineing up. Pick the best side and I like to back off rather than tighten to make hole line up so pick the best side that does not back off the TQ as much but close to 1/4 turn looser.

Ron when I did my cicv trucks I used a wheel dolly and added most of the oil too the hub before install. Then when all axles are done and Diff. is toped off I just park the truck sideways on a grade for 15 mins. then reverse for 15 and then level park then top off Diff again.

Once again your trucks do what you think is right.

I agree,thats about the same way I do my preload on bearings.
The only tourqe that is in the 250 to 400 range is the lugnuts,I think it is 300 ft#
Let me know guys,cause I don't rember any bearing tourques being that high.

 

[Tow4]

Here are pictures from the LO for the M915A1 which uses all modern heavy truck civilian style steer and drive axles.

The front steer axle uses wet hubs. The oil level is not halfway up the spindle, it is below the spindle.



The rear drive axles fill plug is below the axle center line. Remember, the axle housing at the hubs are not as deep as the housing near the center because the housing tubes are reduced and threaded for the bearing nuts. What does that make the opening for the drive axle, ~2.5 inches? Doesn't look like the oil level in the axle will fill the bearings static, and it doesn't.



The LO also shows the procedure to fill the hub. If the oil level was far above the axle center line so the hub would fill, this would not be necessary.



The reason the oil level is not that high is because it's not necessary and the simple act of churning up the oil adds drag and heat. It only takes a small amount of oil to lubricate a bearing and normal operation circulates enough oil out to the hubs to keep them full. That's why all the deuces and 5 tons that have an outer grease seal failure and have the hubs full of gear oil with the grease washed out of the bearings, run cool without problems. A deuce doesn't have an inner oil seal like the 5 tons so the oil leaks out.