Which Direction for Inner Axle Seals

NormC said:
I remembered reading somewhere the required direction for these seals but CRS caught up with me "Where" I read it.:rolleyes: Well, as all of our wives have told us, read the directions dummy.:o There it was in the "Ford Barners" recommended reading, Ford V8 Service Bulletins, figure 184 and 185. The correct orientation of the seals are the lip of the seal facing the brake hub and transmission.

Dick was correct.;)

I don't post much on the forum, but I read it almost daily. There is a wealth of knowledge here that I have quietly enjoyed learning from and continue to learn from.:D

A dog is never too old to teach new tricks to if the dog wants to learn.:)

Thanks to all, Norm
Click to expand...

Norm, you are reading it wrong, For the axle bells it says the sharp edge of the leather of the seal goes towards the differential. That equates to the open side of the modern seal towards the diff.

Agree that the seal at the front of the torque tube is fitted with the open side or lip towards the UJ.

That's a lesson learnt for me, when I replaced the one on Old Rusty years ago I put it the other way around without even thinking about it.

Mart.
 
Last edited:
Ok this is worse than teaching school, It is your car you can do what you want but to validate my point about the seal position here is a copy from Victor Page service book on old Fords that reaffirms my position on the male/female seal orientation.Since the drive shaft inserts rear to front this means the taper of the seal faces the rear. Since an axle inserts to the axle tube from banjo to hub this means the taper faces the banjo as the axle is positioned thru it and the open edge is to the outside.
 

Attachments

  • seal position074.jpg
    seal position074.jpg
    54.3 KB · Views: 245
Dick, You are right on the driveshaft but wrong on the axle. If you look
at the first picture in post 19 it says "grease retainer - install with sharp
edge of leather toward differential". The direction it is installed depends
on which fluid you want to retain not which direction the shaft slides on.
On the axle you are trying to keep the gear lube out of the brakes.
See the August 1933 service bulletins for good pictures.

Bob
 
rotorwrench said:
There is no fast and easy rule since there are always exceptions. On a grease closure, they are designed to let the grease purge out when servicing. On a fluid closure the lip generally is put toward the fluid unless there is a case preasure concern and the fluid level does not reach the closure.

I always wondered why FoMoCo put the grease fittings on the axle housings. Those hubs can't get a good service unless they are removed and hand packed. There is no where for the grease to purge out well enough to get the old contaminated lubricant out. Purging into the rear axle housing is not a good idea. Ford put the seals there to keep the grease out of the axle housing. The fluid level in the rear axle is generally below the axle a good bit so oil leaking out there is generally not a problem. The differentials rely on the ring gear to distribute lubrication to the bearings & gears.
Click to expand...

It is plausible that the axle seal is mainly mainly to keep grease out of the rear axle housing. (To prevent grease being forced past the seal during regreasing via the fitting.) For this "grease retention" purpose, the open side of the seal should face the wheel hub, as I believe Dick is advocating. However, this would not seem to conform to the Ford service bulletins that call for the axle seals to be installed opposite to the driveshaft seal (relative to the differential). Apparently, the driveshaft seal is installed with the open side to the U-joint.
 
I don't remember what vehicle or where the seal was installed but I do remember it having double lip.May have been an OT crankshaft seal. One lip facing one way & the other facing the other way. Might that not solve the puzzle. Don't ask me what the # was or who made the seal. C R S ya know. A good bearing or parts house could look it up tho.
 
The three seals in question, one at the U/Joint, two in the axle housings are there to control transmission- differential fluid. They are not for control of grease!! Transmission fluid will migrate thru the u-joint and back thru the drive shaft tube to the diff. The seal in the front of the drive shaft tube is to control this. So the lip should point toward the transmission. The axle housing seals are to prevent differential fluid from going toward the brakes, not to control over greasing of the drum bearing. The lip should point toward what you are trying to control that is differential fluid.
 
ford38v8 said:
Norm, all such rubber seals are installed with the edge facing the inside. Think of a snow shovel dragged over the snow or pushed along facing the snow.

OK, snow shovel doesn't work for either Ga or Ca, so think of... a paint scraper? :D
Click to expand...

So it took 26 posts to confirm my stupid snow shovel example? Are we a bunch of old guys sitting around the cracker barrel or what? :D
 
Absolutely incredible thread here and I cannot resist commenting :eek: . If I would have had a clue so many think backwards is right on the driveshaft seal I would NEVER have passed on my liking of straight SAE 140 in the u-joint . Not the best choice with a bad or backwards driveshaft seal . David J
 
Well, it demonstrates the superiority of the internet!
Ask a Ford Manual which way 3 seals go, and you get one lousy answer for each. Phooey.
Ask online, and you can get dozens of answers! For free! Can't beat that!
 
Coming from the hot rodding side of things, when a car is lowered it creates the opposite problem. Axle oil migrates to the trans. After a long run my friend has to drain off the excess from his trans and put it into the axle.

Not saying this changes anything, but there's always two sides to any coin.

Having the ford manuals illustrate how they go is great, it takes out any second guessing.

If and when I do the job again I now know what to do. Two innies and one outie.

Mart.
 
What is amazing to me is that number here seem to think that despite having built millions of cars with the grease seals installed per their own service bulletins that Ford did not know what it was doing. This despite the fact that thousands of those cars have survived Ford's failure to understand what purpose these grease seals was to serve.

Dick, my long time friend, you are correct about the torque tube seal orientation. That shows in your illustration and is consistent with the Ford service bulletins. Apart from its obvious purpose in that orientation, the absence of any significant taper on the front end of the drive shaft precludes the seal from being installed backwards; it would be torn up when the drive shaft passed through it.

The taper on the axles shaft is an entirely different matter. It is severe enough to pass through the grease seal with the open or lip side facing the differential in conformity with Ford's service bulletins (and the way the damn things were built in the first place). I've done it that way at least a dozen times and haven't wrecked a seal yet, including NOS leather seals. (Okay, I do have the advantage of having all of the original KRW tools for the job so that helps.)

Kind sir, you are correct about the orientation of the torque tube grease seal, but your argument does not trump the service bulletin instructions regarding the grease seal orientation in the axle housings and the purpose for that orientation which is to keep rear axle lubricant (which has a much lower viscosity) from reaching the rear wheel bearings whose grease has a much higher viscosity. Please think in terms of what would happen to rear wheel bearings running in rear axle lube during extended high speed driving.
 
Last edited:
Overgreasing of the rear wheel bearings may have been the reason why Ford deleted the grease fitting in that area after a certain year.

Mart.
 
Ok one more time, the seal lip on the axle shaft seal is tapered to the banjo to accept the axle during installation. All this hoopla about the rear axle lube running thru the seal is due to a worn bearing or race that causes the axle shaft to elliptically rotate and wear out the seal or place a groove in the axle shaft itself.
If your car is leaking lube thru the axle seal you have about 2 gallons of lube in the banjo that only takes less than a quart so no matter which way the seal is positioned its going to leak or you are spending time playing Joie Chitwood thrill show driver up on two wheels.

Since so many have referred to the service bulletin books I started doing some research and will concede that although one section explains it contrary to my opinion I believe this is a mistake created by the instruction writer that was only looking at a bunch of parts laid down incorrectly in front of them for reference purposes and the sequence written about was just made up text even though it may not have been correct because it followed the similar from truck axle installation.

Anyway I'm standing firm at the present time because I got my KRW axle seal installation tool out and got an NOS seal and a new Repro seal and there is no way you can install that original leather seal with the lip facing in without crushing the leather during installation. Put it together with the lip facing out goes right together.
 
Dick,

Yes you can if you follow the old rule about soaking the leather seal in motor oil for at least 24 hours.

Dave
 
Having been a professional mechanic and having worked almost everything you can think of that runs across the ground or water for nearly the last 40 years.
Iv never seen a seal that didn’t install like I’ve marked this photo.

409232262.jpg
 
This is one of the items that will always have some contention but I think there is no wrong answer on this. If you look at the parts nomenclature for the seals they are largely refered to as grease retainers and That is likely how it all started. FoMoCo put those grease fittings in there and the port is right outboard of the retainer or seal. Grease will take the path of least resistance and the seals were probably originally designed to hold the grease from going into the axle housing instead of going into the wheel bearing. Unfortunately, there is also the possibility of contaminated grease being forced into the brake drum. The service bulletins were to make procedural and parts changes. If complaints of grease in the drum were a problem then they were limited on how they could effect an alteration that would rectify any and all possible problems. Turning the seal around would give the grease a place to go other than into the drum for those that believed you had to keep greasing until it came out somewhere ( you all probably have know folks that think that way). Filling the rear axle was preferable to filling the brake drum so they flipped the grease seal around. Later they deleted the grease fitting and gave instructions to hand pack the rear wheel bearings. The grease retainer became an oil seal to keep axle lubricant in the axle. Problem solved?

Here we are years and years later and still having a problem with direction. The truth is, it really doesn't matter which way it goes unless you park the old fliver on the side of a steep grade and all the rear axle gear lube runs into the low side brake drum.
 
Well there has been some great dialogue on this topic.:) Thanks to all who have given their 2 cents. A wealth of knowledge as usual from you guys.

Still in a quandary as to the orientation of the seal. Am I keeping oil out or grease.:confused: Maybe I should experiment one each way?:eek:

Thanks, Norm
 
I always wondered about those cars that park side on on the steep hills in San Francisco. They must have had one brake full of axle oil.

san-francisco-1940-1950-7.jpg


Mart.
 
Last edited:
You must log in or register to reply here.
Back
Top