1959 rear axle seal replacement

[65mod]

Hi all, new member and finally an owner of a 1959 Cadillac Sedan DeVille Flattop.
I have a leaking rear axle pinion seal and can't find a replacement size. Seems to be two options from my research so far. One is 3.75 inch outer diameter and 1.75 inch inner. The other is 3.25 outer and 1.875 inner. Got me really confused. Don't wanna pull it apart and not be able to source the correct part as I'm in Australia and these parts can be slow in arriving. The cast number on the front of the diff housing is 1468755 as I read this can help somehow. Can anyone help a newbie please

[The Tassie Devil(le)]

G'day Alistair,

Welcome.   I believe the '60 parts are the same, and therefore the seal is available through Rock Auto  https://www.rockauto.com/en/moreinfo.php?pk=1839734&cc=1320512&pt=2380&jsn=442 

But, first try All American Auto Parts in Ballarrat.    https://www.allamericanautoparts.com.au
  They are really good suppliers of Cadillac and other GM parts.

And very easy to deal with, plus a simple phone call away.

Bruce.

[65mod]

Hi Bruce
The bearing size you referred me to at rock auto is the other size that comes up which is 3.25 inch outer diameter and 1.875 inch inches inner diameter. The one I thought I needed is 3.75 inch outer and 1.75 inch inner. The two sizes pop up everywhere for this model in all my research but no one can clarify this for me. The bigger one seems hard to find as I have looked at various bearing/seal outlets. I don't want to pull the seal and not find a replacement hence I'm unsure of which part is correct. The number on the diff carrier is 1468755. One site said this was important somehow but no reason was given. Sorry for my cluelessness but this has me stumped. I have emailed All American Auto parts and waiting on a reply.
Thanks for your help.
Cheers
Alistair.

[The Tassie Devil(le)]

Could it be that the larger one is for the Commercial Vehicle.   From what I am recalling, these had a larger rear end.

I take it that you have the Shop Manual?

Bruce.

PS.   Not sure if you can get to it as the slinger on the yoke might limit access, but I would be lifting the car, and physically trying to measure the seal whilst it is still in there.   This can be done with the tail shaft attached.   I just looked at the pictures I have of my old '60 CDV, and there isn't much rook between the slinger and the pumpkin.

[65mod]

I have been looking through an online manual but it doesn't mention sizes. The seal I need is near the wheel and it is leaking onto the brake on the passenger side only.
I will try and see if I can get the rear wheel off and see if I can get a measurement. Just my luck that I can't get a simple solution lol. Lots of places seem to have the smaller one in stock but the bigger one is hard to find.

[Daryl Chesterman]

Alistair, below is a copy of the page in the parts manual for the pinion seal.  While looking at the parts manual, I could not see the 1468755 carrier number that you referenced.  I think, like Bruce said, it is best to clean things up in that area and see if you can determine a measurement.  Failing that, you will need to drop the propeller shaft and remove the yoke, being sure to follow the directions in the shop technical manual exactly.

Good Luck!
Daryl Chesterman

[The Tassie Devil(le)]

I have been looking through an online manual but it doesn't mention sizes. The seal I need is near the wheel and it is leaking onto the brake on the passenger side only.
I will try and see if I can get the rear wheel off and see if I can get a measurement. Just my luck that I can't get a simple solution lol. Lots of places seem to have the smaller one in stock but the bigger one is hard to find.

Alistair,

I think we are looking at the wrong seal.

The Pinion Seal is in the front of the Diff Pumpkin, and directly behind the tailshaft.

The Axle seal is a totally different kettle of fish.

This one is an "O" Ring that is around the rear axle race, and the re is a cover on the side of the race to keep the diff oil inside the housing.

If the "O" Ring is leaking, then that can be replaced, but if the oil is coming out through the bearing, then  you will need a new bearing.   These are not cheap.

Plus, you will need the Shop Manual for the correct measurements for the race to be positioned on the axle.   Or, we can give you the measurements, but having the Shop Manual is far better, as you will need it.

Bruce.

PS.   Having the correct terminology is good, and required.

[65mod]

Thanks for clarification. I'm not a mechanic but the mechanic that looked at it for my roadworthy said axle pinion seal but it is definitely the one at the wheel end and leaking onto the brake. Going to pull the wheel and have a look. Sorry for the confusion. I am happy to learn as I go. Thanks for your help

[The Tassie Devil(le)]

Well, to fix it, the axle has to be pulled, and if the shield between the inner and outer rings of the bearing is good, then it could just be the "O" Ring.

It could be a simple fix by going to Repco and getting the correct size "O" Ring and fitting it.

These axles don't have a normal Axle Seal, like say the Ford 9", but the "O" Ring stops the oil from slipping out between the outer bearing ring and the housing, and the seal between the bearing rings.   I have always replaced the whole unit, as the bearings were suspect.

This from Rock Auto shows the seal and "O" Ring  https://www.rockauto.com/en/moreinfo.php?pk=1838144&cc=1320523&pt=1860&jsn=476
And this from Rock Auto shows the bearing, with the seal fitted.
https://www.rockauto.com/en/moreinfo.php?pk=11699757&cc=1320523&pt=1672&jsn=483   

Bruce.

[cadman59]

At this very moment me and my son are rebuilding the complete rear end of my 1959, what also started because of leaking axle seals. The Pinion seal also already leaked (sweat-ed) for years.

This is what a leaking axle seal will look like:


This is what a leaking pinion seal will look like:


The seals of both Pinion and rear axles were really worn.

As Bruce says, the axle seals are part of the axle bearings so you would have to replace them as a unit.

New rear axle bearings in place:


New pinion bearing in place:


Since all the bushings, spherical joint, springs and shock absorbers were also in a bad shape, and everything was rather rusty, we decided to to it all now that we are at it.

[Roger Zimmermann]

Well, to fix it, the axle has to be pulled, and if the shield between the inner and outer rings of the bearing is good, then it could just be the "O" Ring.

The chance that only the "O" ring is leaking is very small. Usually, the whole bearing must be replaced. Fortunately, there is only one size for all 1957 to 1965 cars, exc. CC models.

[Jon Riley #13576]

This video shows replacement of the o ring

https://youtu.be/djKwbdMnH8M

[Roger Zimmermann]

Really, I'm not convince that the leak came from the O ring. That '59 car still has the old style bearing which is lubricated by the rear axle. After so many years, the seal at the outside of the bearing must leak. It will be the opportunity to make another video "how to replace the rear wheel bearing"...

[dn010]

I just went through this on my 57. Oil leaked into the drum and got all over the shoes. Was a mess. Bearing is sure to be the culprit as opposed to the oring. Pick a good bearing that isn't a China-bomb. Good luck.

[gkhashem]

It is one of the two on Rock Auto.

I did mine in 2020 and had the same issue so I bought both.

Sorry but I cannot remember.  However one of these will work I am sure of that. I will check as soon as I am able. I think it is SKF18922.

SKF 18922 {Click Info Button for Alternate/OEM Part Numbers} Info
Rear; Carrier No. 1473735 & 1473782
   
<
   Part image   
>
   $10.08    
      
Add to Cart
SKF 18948 {Click Info Button for Alternate/OEM Part Numbers} Info
Rear; w/o Carrier No. 1473735 & 1473782


As I read through the posts SKF 18922 looks like the one in the photo above.

[dn010]

Trouble is he needs a bearing, not a pinion seal. Title confuses the thread.