PENION SEAL

[51willysm38]

You might also check your yoke to see if there is a ring worn around it. If there is it won't completely seal even when the seal is new.

[MSeriesRebuild]

NOS leather or other leather seals are simply notorious for wearing a ring on the yoke seal surface, rubber seals of today don't do that. That felt dust shield on an NOS seal gets wet and holds water like a sponge keeping that area of the yoke wet also, that's why so many are eat up with rust pits. Either of these situations are certain death on a yoke when it comes to oil leakage. While NOS seals were the technology of the day in the 50's, they were and continue to be bad news for yokes, we haven't used an NOS seal in years. Today's technology with redi-sleeves has literally been a God send to repair the damage NOS seals typically cause, however some are damaged beyond the point of a redi-sleeve saving them in cases where die-hards simply insist on continuing to run NOS type oil seals. Really good advice for anyone still using NOS seals, get rid of them now. This applies to every seal in every component on the entire truck, not just differentials.

[WarrenD]

That's all well and good, Charles, but everyone I've talked to says there is no aftermarket replacement for the pinion seal. Do you know something different?

[MSeriesRebuild]

You haven't talked to the right person. We had to work a solution for the trucks we build. We don't send trucks out with oil leaking, period.

What we did was custom machine an adapter that presses into the housing; we did it so a current production double lip oil seal presses into the adapter. It is designed so the seal can be replaced if need be without removing the adapter from the housing. We also included threaded holes in the adapter so it can be easily pulled using a common puller should it ever need to come out, such as for bearing replacement or gear set changes. It can be pulled multiple times without worry of damage, it's built to last the duration.

As with any custom built component, it isn't cheap because of material, (1018 cold roll) and machining cost. It includes the oil seal, (pressed into the adapter by us), and a redi-sleeve for the yoke. Cost is $135 for the kit. We've had excellent results with these as long as close attention is paid to be sure the the redi-sleeve is pressed onto the yoke at the correct distance so the seal lips are centered on the new sleeve surface. We've tried other lower cost solutions that were hit and miss, but none were successful like these kits have been.

[WarrenD]

Thank you Charles, I'll keep that in mind should I need to replace my pinion seal again.

[Cal_Gary]

Trying again:

[Cal_Gary]

And more-again, this took less than 10 minutes:

Hope this helps!
Gary

[MSeriesRebuild]

Be sure and not get too aggressive. It is easy to crack the bore flange on the housing with heavy equipment; remember it is a casting. What we typically do with the ones that prove stubborn, (about 50%) is heat them up with a rose bud, they generally surrender quite easily after that.

[Cal_Gary]

(Speedy sleeve also went in where the seal replacement was completed).
Gary

[Sal]

This is the tool I used to remove the old seals on the transfer case while it was still in the truck, They came out pretty easy.

SEAL PULLER.jpg (2.92 KiB) Viewed 2113 times

[MSeriesRebuild]

This is the tool I used to remove the old seals on the transfer case while it was still in the truck, They came out pretty easy.

SEAL PULLER.jpg

This type seal extractor works very well in lots of applications also. They used to be sold off the Snap-On truck. Not sure if they still are, as we no longer have a Snap-On rep working this area.

[MSeriesRebuild]

Gary, are you working on an M37? The yokes pictured are common to the civilian power wagons.

[cuz]

Modern Garlock lip style seals are not exempt from causing grooving of companion flanges and yokes. If you get enough abrasive material like dirt and sand and silt against them they will saw the same the groove in any shiny surface. The old leather seals are coarse then the modern rubber lips and will hold grit and wear things faster.Trailer queens and city drivers will not have issues for years but those folks four wheeling will see those grooves with either seal if they don't either protect the lip from the foreign material or clean it immediately after mudding, sand bogging or fording.

[MSeriesRebuild]

Proper clean up,care, and maintenance after mud bogging, etc is imperative. These types of situations are why seal manufacturer's offer no product warranties. It is a matter of common sense in realizing that poor maintenance in regards to the type of operation can lead to damage and a shortened life of any component, be it a seal or anything else. A double lipped current production seal stands a far greater chance of a long life without debris inflicked damage on a yoke than does 60 year old leather and felt seal technology. Leather will cut metal in the cleanest conditions. When sharpening knife blades, I always finish the job with a few strokes on a leather razor strap to finish up with a clean edge. Ever wonder why they never had rubber razor straps? It's because rubber doesn't have the same cutting effect as leather does when rubbed against metal. The same principle can be applied to leather seal material cutting a groove in the yoke it mates with. Do you think this may have something to do with why leather seals aren't widely offered these days? They do still exist for use in a very few applications, (not automotive applications) but where for one reason or the other, rubber material is not compatible.

I don't say this in the spirit of starting a massive argument, what I do say is strictly based on factual data that we have had opportunity to see proven many times in many different applications. What we deal with is building trucks that are used in numerous different types of situations. I haven't seen one yet with current production oil seals that were installed carefully and correctly that didn't far surpass an NOS oil seal in seal longivity with no significant damage to the yoke. We came up with our pinion seal upgrade kit for use in the differentials we build in house. #1, I don't send trucks out with leaking seals, thus we had to come up with a way to stop dripping that is almost 100% certain with NOS seals, using a redi-sleeve in combination with a leather seal does not stop the drip. #2, yokes don't grow on trees; so using seals that you know will cause damage, even in a clean environment is in my opinion not a smart decision. #3, if our upgrade had not proven to be a solid solution to the afore mentioned issues, we surely would not be installing them in components that we build here; but would instead still be searching for a solution that worked. Whether we are dealing with rebuilding a single component, or doing a 100% restoration of a vehicle; our goal is to turn out the best quality component or vehicle that money can buy. Obviously that is no cheap endeavor these days; honestly offering the best quality rebuilt components and restorations has kept us busy, with a backlog for years doing both long term restoration and run in type projects. Bottom line is plain and simple; if I don't know it works well, you won't see it offered at our shop. Some ask if we refuse to install NOS seals? The answer is we will install whatever the customer specifies; however if NOS seals are installed in a rebuilt component, we will not offer a warranty on that component. We normally do offer warranty on rebuilt components provided that component is built in accordance with our guidelines.

[Cal_Gary]

Hi Charles and All,
Yes, that's in my 1954 M37-my old T-case has a rebuild tag by Aberdeen Proving Ground dated 1975, and it had those Y-shaped yokes on the bottom, front and rear (until I swapped transfer cases-had to swap the yokes as well).
Gary