What do I need for a rear axle seal replacement?

[Jeepsinker]

Man if you can develop a "bolt on kit" so to speak that will keep oil in these hubs I'd be all over it.

Me too!

 

[Jeepsinker]

I'd comfortably spend $300 per axle for a bolt on kit.

 

[welldigger]

I have so many prototype projects going on right now it would have to wait.

Fair enough. But, if and when you do count me in.

 

[socom688]

Doghead, I have not. They have 1" hose on them for a snorkel kit. Could they simply be clogged? But my seal still would need to be replaced even if I unclogged/adjusted it correct?

 

[doghead]

If your vent is plugged, it will cause leakage.

Many times simply cleaning the vents stops the leakage and the seal does not need to be replaced.

Depending on how bad it has been leaking, you may or may not need to disassemble and clean everything.

If you have never serviced/cleaned your axle/hubs, you should do it once, then maintain as needed.

 

[Lieutenant Dan]

Does anyone have the tm where I can find the procedure for this with torque specs? I've been searching and can't find it

 

[doghead]

does anyone have the tm where i can find the procedure for this with torque specs? I've been searching and can't find it

tm 9-2320-361-20

9-4 rear hub and drum maintenance

 

[Floridianson]

The oil in the hub is very likely caused by a failed keyway plug.

I respectifully disagree.
If you look at the rear the oil fill plug is just about level with the bottom of the axle tube. So to me the hub could never carrie anything higher than the lower part of the axle tube or it would drain back to the chunk. The key way is on top of axle tube and seems like the only way it could ever have oil around it for any time would be when the truck or rear is cocked to one side for a good while then when level again it would drain back to the chunk leaving just the amount the hub can carrie up to the bottom of the tube. Im not saying that the key way will not let oil in but I vote for seal being the major leak letter. I also found on some of the axles I have done is how loose the nut/bearing is and that a loose seal would let oil pass by. If you look at a civvi semi truck the fill plug is higher ( half the tube ) because it needs to carrie oil out to the inner and outer bearings of the hub as they are oil bath type. MY.02

 

[TMNT]

Just going off of my somewhat limited experience on my truck. I troubleshot repeat occurrences of oil in the hubs. I never found anything wrong with the seals, but in every case the keyway plug had either failed (original cork) or the silicone had not been properly applied (my fault). I cleaned everything up, put it back together with the same seals, properly plugged the keyway and no more problems.

Of course, there could always be a worn out or loose seal, but my experience was with keyway problems. I've read plenty of posts by others that had similar issues.

The bottom line is that it must all be in good condition and properly installed to prevent leaks.

If the diff lube is filled to within 3/4" of the fill hole, it only takes a couple of inches of tilt to one side to dump a good bit of lube toward the low side hub. If the keyway is not sealed, the lube sloshing and splashing in the hub gets through the keyway, and then it is essentially trapped in the hub. That's my theory anyway.

 

[Floridianson]

Yes the keyway has to have something in it. I think silly cone is for breast inplants and have used paper towels and have not had a leak so far. I use a small flat blade screw driver and cram as much paper towel in there as possible. I do keep my bearings tight and never do the tighten then back off and don't use a touque wrench and no problems as of yet. I tighten down to about 50 lb spinning the hub. Then I back off a half turn then tighten again to what I feel and no back off. Maybe some don't tighten enough and the bearing after running gets loose and lets the oil get by the seal. I have serviced large civi trucks for many years and never had one I
over tighten.

 

[frank8003]

You asked what would you need to do the job on the ninth.
If the seal in the keyway was omitted or has failed then assure you have a good seal when YOU fix it.

 

[steve6x6x6]

The oil in the hub is very likely caused by a failed keyway plug.

I respectifully disagree.
If you look at the rear the oil fill plug is just about level with the bottom of the axle tube. So to me the hub could never carrie anything higher than the lower part of the axle tube or it would drain back to the chunk. The key way is on top of axle tube and seems like the only way it could ever have oil around it for any time would be when the truck or rear is cocked to one side for a good while then when level again it would drain back to the chunk leaving just the amount the hub can carrie up to the bottom of the tube. Im not saying that the key way will not let oil in but I vote for seal being the major leak letter. I also found on some of the axles I have done is how loose the nut/bearing is and that a loose seal would let oil pass by. If you look at a civvi semi truck the fill plug is higher ( half the tube ) because it needs to carrie oil out to the inner and outer bearings of the hub as they are oil bath type. MY.02

 

[frank8003]

It could be the leaking wheel cylinder, no seal in the keyway, worn out brake linings, rotted, twisted steel brake lines, really sad rubber brake lines, missing fastners, etc and just a mess.
Truck don't go anymore until fixed.
See something like this and you then know you have the other five axles to fix too.

 

[steve6x6x6]

Your thinking in horizonal position, these trucks are never horizontally, leaning severely to the right and left and the oil inside piles up, way up inside the axle tube.

 

[Floridianson]

OK I can see that Steve and would never doubt that the key needs to be addressed with something. My thought was more along the lines of seal being to loose.

 

[gringeltaube]

Your thinking in horizonal position, these trucks are never horizontally, leaning severely to the right and left and the oil inside piles up, way up inside the axle tube.

Agreed. But don't forget that even in the (hypothetical) case that it always remained perfectly horizontal, during operation oil always gets on the axle shaft ends and from there, creeping outwards along the shaft, and finally collecting into the cavity between axle flange and (outer)seal. Once there is a puddle there it only takes a few revs to have oil all over the place and possibly into the keyway...


G.

 

[Floridianson]

On Frank's picture I see nothing wrong. Well lubed bearing and antilock forward shoe brake system greased and looking like it won't lock up. Where is the problem?

 

[frank8003]

seal, the famous seals


the keyway ......................
**** thing should be famous

anyhow I need a bunch of these squish seals...#1 in the drawing (#1)
Please say where to get a dozen or so .... best price?

 

[Floridianson]

Are you guys checking the grease slinger plate holes to make shure they are open. What I have found if the wheel cylinder goes bad it will get the shoes. If the slinger plate holes are open through the drum the grease from the hub will exit and be between the tires on the outside of the drum.

 

[Lieutenant Dan]

I got a handful of the cork plugs from gibb this weekend. They are the right nsn part # the tm calls for. They measure 1/4" wide by 3/8" long by 3/16" thick.