Where do you buy maintenance parts? is now WIDE RANGING maintenance insights on parts and techniques"

[jacwjames]

Also check to see if you feel any movement in the yoke.  Some thing is causing the seal to leak and bearing failure is a possibility.  Also make sure the vent is open the allows the differential to relieve air as it gets hot.  If not a pressure build up might cause seal to leak. 

[Jetjockey]

I am with James. Pull drive shaft off differential.Feel for endplay and side to side.you actually can do this before and after drive shaft removal. I have used dial micrometers with a magnetic base. Set micro meter up. You can then check up, down and endplay. Not sure what is acceptable in this application but it will give numbers to the movement.

If there is a large nut holding yokes to differtial.then scratch index marks on both for reassembly . Torque wrench is best but I have done both ways.  There are tools made for pulling old seal. Hook as jwj descibed. Pull oil seal,clean and install new seal with seal tool which will engage the whole seal circumference for equal seating pressure  . I have used a socket large enough for the seal to fit the seal circumference .If there is an intermediate carrier bearing,check to make sure it is doing its job of stabilizing shaft. On short driveshafts there may not be one. But you definitely want to look at all connection points. The comment about checking the vent first it a good one. I would check it first. it usually  is a spring loaded small cap on top of case. Pull up on it slightly turn a little in both direction and let it back down. Sometimes you can hear air passing the vent if plugged.Or the vent could be A hose or tube,make sure it is clear. What ever the vent, it will be on the top half of differential.
Or locate the fill level plug on differential . Slowly remove it. If pressure exists from plugged vent you will hear it or feel it as you remove the plug.

as long as differential is the kept full  . I would not be concerned about driving it. Just make it a point of inspection. Until you decide your solution. If the venting was plugged an caused pressure as everything heated,clearing vent may stop the leak . A plugged vent can do the same on axle bearings.good luck. My post too long again. I don’t think it would take any longer do the job,than this post takes.

Edited February 26 by Jetjockey
Addit

[Just Jim]

No Jet, that was great info.  Thanks for taking the time to post it.  I've also seen people discuss some type of "stop leak" if everything else checks out.  I've used that before on an old car.  Not sure about on something like this.

[Just Jim]

Pictures of the Diff for your viewing pleasure.  There is some moisture around the vent tube, but did not try to check it or anything else.  Just took some quick pictures.  I found in my literature that the diff and axle are Dana with a model on the differential of 21060S

[Chargerman]

I definitely would not put any type of stop leak in my differential, or anything else for that matter. As Jet mentioned, it is not a difficult job and if you decide it’s a little much for you to consider it should be crazy money to replace it. Guessing a competent garage would charge around 2 hours time plus parts. Might be the right time to change the gear lube also. 

[jacwjames]

Your U-Joints look pretty dry, when was the last time they were greased?  Try greasing them and see how much grease you have to inject to get grease to come out the ends. 

If you do have to remove the Yoke I'd consider new U-joints.  

[Just Jim]

I noticed that as well Jim.  I have greased the front, (and they were not bad) but have not gotten to the rear yet.  Once I actually get under there and get dirty, I'll check it for play and grease it, check the vent and check the oil level.  Then can make a decision on how to proceed.  I do have a shop that I've used before that does good work.  I wouldn't mind doing it myself, except I have a drip scheduled and not sure I'll have time to do and/or if the weather will continue to cooperate.  Thanks for the insight everyone. 

[Jetjockey]

No stop leak for me either. Sometimes factory ujoints don’t even have a grease serk. After market usually do. I would agree that replacement of u joint is alway a good idea while you are there. It makes one feel a lot less foolish if it later fails.although I will admit I do not always replace . Usually involves replacement on both ends of shaft.I use an infrared temp gun to shoot temps after having driven. You develop a crude baseline for normal. If even one of the yoke cups is sticky you will be able to see it. I used to just slide under and touch them until I got burned on a hot one.

does the drive shaft telescope enough to remove the nut and slide the yoke off input shatter ?Those nuts are heavily torqued.you have to have a wrench that can engage well enough to get it loose. 
It appears some residual grease is inside the yoke by the bearing cup..Good sign ,some one has greased it. Ujoints can be a little or lot tricky to replace. Including having them relieved of friction once installed.the size and weight of this driveshaft will aggravate the job. 

Pictures show rust,corrosion and deterioration of the threads on the shaft. That can really make this difficult to remove . Maybe a good reason to let your shop have at it. Or you  get to a position of being part way disassembled  and unable to finish. You never know. Those threads look to me like a challenge. Plus the flats on the nut are not made very deep and they also show erosion. Fun fun.

 

 

[Ivan K]

You would likely also need removal and installer tools for the ujoint cups, looking at the corrosion. There's no space for a sledge hammer like truckers might use. These are not like the usual automotive joint straps.

[Jetjockey]

I have replaced these while on the semi. Everything has to go right.in some ways they are easier than a pickup. In other ways harder.I have used a small hydraulic bottle jack to press them out and in. Unless you are real comfortable with doing this ,it can deteriorate into a mess. There is some technique and feel that is involved with this repair. Good luck

Edited February 27 by Jetjockey
Addit

[Tom Wallis]

Replacing the pinion seal would not be considered a big job for an experienced mechanic but it could pose some problems for the novice. I wouldn't use a stop leak. I would replace the ujoint without question. Don't worry about getting a micrometer to check the pinon bearing, it is preloaded and should always have zero play. If there is play of any amount, take it to the shop. The ujoint shouldn't be hard to replace but the hard part will be the pinion nut. It is installed with a great deal of torque and you'll need a 3/4" ratchet and probably a cheater or a 3/4" drive air impact to get it off. Not all 3/4" drive sockets will fit inside the yoke to get on that nut either.  You don't necessarily need a slide hammer to remove the seal but that's the easiest way. When installing the new one it best to have a piece of pipe or something about the same diameter of the seal to drive the new seal in. Make sure the seal surface on the yoke is clean and smooth before reinstalling it.

[Jetjockey]

Tom w. Good to see a real mechanic chime in.
 

Clean up prior to installation is a must. I usually use emery cloth to clean and polish yoke surfaces where the cups must slide thru. This putting in a new ujoint is probably beyond the experience level of most of us here. If you have never done one on a car or pickup, this is not the place to start.

while you can remove the old one destructively if nescessary, pressing the new one in is a different task. I have done a lot of ujoints and I never have enjoyed it.

[Just Jim]

Thanks for all the great info.  I'm thinking at this point that I'm going to check with my shop and see if he will do it.  I like the idea of replacing the U-joints as well... makes no sense to take it apart and not put back new and I think the yoke nut is a one time use item??? 

How would I find part numbers for the U-joints? 

It does not look like replacing the pinion seal is a big deal (for the right person); would you say the same if also replacing the bearing?  Again, seems to make sense to do it if you have it apart, as long as that does not add a bunch of hours of labor, etc.

Jim

 

[jacwjames]

If you decide to try attempt this yourself mark the drive shaft for alignment, it has to be in phase otherwise you'll have vibration and eventually more problems.  Your driveshaft may already  have marks on it. 

Also, while everything is still together I'd take a pry bar and see if there is any movement in the U-Joints, as dry as the one in the picture is it may be getting ready to fail.  If there is play it may have caused the seal failure as it would have caused the yoke to rock and roll as you were driving down the road.  Since the coach is new to you it would have been hard to distinguish any vibration unless it was really bad.

 

Back in 2015 I had to have my radiator changed, road debris took it out, luckily it was an insurance claim.

I had Cummins do the work.  When I went to pick it up I had about a 45 mile drive home, as soon as I got on the interstate I felt a slight vibration, got home and crawled under the coach and saw that driveshaft was out phase.  Must have had the B team putting it back in.  I pulled the drive shaft and also saw a problem with the U-Joint, I carried a set so I changed out that one, had a heck of time getting the caps out/off, I didn't have a tool but managed to get it changed.  

So even if you have a shop do the job, double check their work. 

 

 

6 minutes ago, Just Jim said:

 

How would I find part numbers for the U-joints? 

Jim

 

5-279X 5-279X Dana Spicer U-Joint 1610 Series w/
Hardware-5-279X Dana Spicer U-Joint 1610 Series
w/ Hardware
 

 

[Tom Wallis]

3 minutes ago, Jetjockey said:

Tom w. Good to see a real mechanic chime in.
 

Clean up prior to installation is a must. I usually use emery cloth to clean and polish yoke surfaces where the cups must slide thru. This putting in a new ujoint is probably beyond the experience level of most of us here. If you have never done one on a car or pickup, this is not the place to start.

while you can remove the old one destructively if nescessary, pressing the new one in is a different task. I have done a lot of ujoints and I never have enjoyed it.

Yes, I didn't say much about the ujoint r&r but it can be tricky also. Polishing those hole inside can definitely help with reassembly. I usually just use a big hammer for disassembly and if replacing the ujoint not much care is required. When installing ujoints much care has to be given to getting both sides of the yoke into the cups and keeping both sides engaged before any hammering or jostling occurs. 

I often get asked if something is easy and my favorite reply is "Everything is easy if you know how to do it."

13 minutes ago, Just Jim said:

It does not look like replacing the pinion seal is a big deal (for the right person); would you say the same if also replacing the bearing?  Again, seems to make sense to do it if you have it apart, as long as that does not add a bunch of hours of labor, etc.

You might try replacing the pinion seal but I would not recommend trying anything with the pinion bearing unless you detect a problem with it. That is a much more complicated job and not recommended for the inexperienced.

[Just Jim]

2 hours ago, Tom Wallis said:

You might try replacing the pinion seal but I would not recommend trying anything with the pinion bearing unless you detect a problem with it. That is a much more complicated job and not recommended for the inexperienced.

Thanks Tom, My reference to the bearing replacement was related to shop cost not me doing it.  If I'm paying to have the U joints, pinion seal replaced... I'm just wondering if having the bearing replaced adds significant time/cost to the repair?  If its insignificant then is it prudent to just change it while everything is apart?

[jacwjames]

Here is a parts breakdown on the rear axle, it shows the different models so you'll have to find the parts for your model. 

I think if the problem is the bearing it is a much bigger job as it takes quite a bit of work to set up a ring and pinion correctly for proper clearances so that the pinion mates to the ring gear correctly.  Shims have to be added or removed and the fit checked.  The chunk probably has to be removed.  I've seen it done on large mining axles, I know enough to be dangerous and would never attempt that myself. 

 

 

Eaton Axle AXIP-0031 Parts breakdown.pdf

[Tom Wallis]

Replacing the pinion bearing is not a maintenance thing. It's not something to dig into unless there is a problem. I doubt there is a problem with it but if the shop replaces the seal for you they will know if there is an issue. Otherwise it's just a seal replacement.

[Just Jim]

I pulled the transmission dip stick just to look at the fluid... somewhat yellow in color?  Right beside the trans dip stick was a 110 v cord attached to the engine.  Is that a block heater?  I knew it has an engine pre-heat from the aqua hot, but not an electric one.  The cord was just hanging down into the engine... right above the exhaust.  I'm going to zip tie it up and out of the way.

[Ivan K]

Yep, block heater. Should have an outlet in its reach. I just keep it plugged in eventhough I never needed to turn it on but never know.

[Dr4Film]

Yes, that's the Block Heater. It should be close to the duplex it would have been plugged into if you didn't have the Aqua-Hot. The cord should have been zip-tied and secured in a safe place.

[Jdw12345]

One thing to look at is wheel seals too, if you’re not familiar with them you have to look at them from the brake side of the hubs, if you happen to have a wheel seal leaking also it’s possible that it’s indicating an issue with the differential, thrust washers, bearings, ect. Just something to stick in your head, it unlikely to have two seals leaking at the same time, metal fragments floating around in the lube will cause multiple or reoccurring seal issues. Just something to know.

Edited February 28 by Jdw12345

[Just Jim]

Good info there.  I had the rear wheel seals leak on my old coach and replaced them as well as the brakes since they had leaked all over.  I don't see any sign of that on this coach, but have not done a through inspection in the back yet.  I am hoping to get it jacked up and supported well this weekend and tackle the trans and hydraulic fluid.  I'll do a good check of things while the transmission drains.  I've heard they will train for hours, so should have plenty of time.

[96 EVO]

1 hour ago, Ivan K said:

Yep, block heater. Should have an outlet in its reach. I just keep it plugged in eventhough I never needed to turn it on but never know.

Yeah, that works if you have an on/off switch inside the coach.

I don't!

[jacwjames]

Check you dash and see if you have a "Block Heat" switch and a breaker in the main panel.  If you do that would control power to the outlet that is mounted on the rear firewall. 

But need to make sure the outlet works.  I checked mine a couple years ago and the breaker would not work, had to replace.  On mine it was a 15 amp GFCI breaker.