Rear VW Axle Maintenance

Rear Axle Maintenance

Not long after I had reassembled Baby, our 1967 Savanna Beige Sedan, I noticed that the passenger’s rear axle was seeping fluid onto the backing plate. “Rats!” I thought.

And, sighing, I got out the tools and began the task of replacing the axle seal—what else could it be? I had done the “taste test” (not recommended for the weak of stomach). It definitely was not brake fluid. Now, folks, I don’t actually imbibe what I taste—it’s an immediate knowledge and I rinse my mouth of any possible residue. It’s the humble chemist’s unfailing test! Some people get a dab onto the forefinger and by rubbing between forefinger and thumb can sense what type of fluid they are dealing with.

Sure enough…after getting into the bowels of the axle, it was a leaking seal. I fetched a new seal pack from my supplies.

#2 RearAxleMaintenance 002

After cleaning things well and making sure that I had not polluted the new brake shoes, I installed the new seal and buckled up the wheel. Done!

But, I’m here to tell you that not long afterwards, I noted that the same wheel was leaking again. Frustration reigned. I called my trusted VW mechanic and cried a bit on his bony shoulder.

Now not all mechanics will reveal their trade secrets. Barry is different. He’s not afraid that I am going to steal his customers. I have no interest in repairing others’ vehicles. So, he spilled his guts. It was so simple that I almost missed it—thought that I hadn’t understood.

But first…a little background.

Through year 1968, VWs have sported a single-piece axle which is connected to the transmission. The axle is encased in a tube which bolts to the transmission housing and to the spring plate structure at the outer–wheel end. Tranny fluid courses at will inside this tube, lubricating the wheel bearing.

Through year 1964, Volkswagen installed a bearing cover onto VWs into which the seal had been pressed into the outer surface. If the seal failed, and ultimately it would wear out, the transmission fluid seepage would exit around the axle and out into the drum. This seepage would transfer to the brake shoes reducing braking power and building a greasy glaze inside the drum and on the shoes.

#3 RearAxleMaintenance 003

#4 RearAxleMaintenance 004

In order to cope with this eventual seal failure, VW had early developed a complicated set up, including a special rear brake drum and little “spoon-like” troughs which were intended to funnel the seepage away from the brakes and out of the drums. The truth of the matter is, these drums are no longer available. Some, like my VW friend who has a restored 1957 Beetle, are fortunate to have a viable set of rear drums, set up as they were meant to operate. There is a solution to this lack of parts situation–but, that’s for another time and another venue.

Well…let’s fast-forward to 1965. VW decided to amend the situation. Engineers had been at work to solve the problem of seepage, wanting to simplify the mechanics of the matter. And, like most improvements, simplification usually also means cost-cutting. Rather than to install the seal into the outer portion of the bearing cover, they devised a new bearing cover designed to be a self-contained unit. Inside the bearing cover, VW installed a loosely fitting “oil slinger washer”.

#5 RearAxleMaintenance 005

This “slinger” actually is loose enough inside the cover that it does just that—it slings about as the axle turns. The hole on the outer surface of the bearing cover, which we see when we remove the drum, is just small enough so that the slinger washer cannot escape. The inner diameter of the washer is just larger than the diameter of the axle itself. The “compartment” in which the slinger works is about 1/4th inch deep—allowing some “slop”.

Now, instead of pressing the seal into the bearing cover from the outside, the seal was pressed into the inner recess, holding the slinger captive. A side note here: New slinger washers are no longer available. My advice to ’67 owners is to have a spare or two. These can be obtained from salvage yards. Remember—the slinger was used from 1965 through 1968. This helps to make supplies of used slingers available. Slingers also were used on vehicles other than Beetles, increasing the chances of finding good used ones.

#1 replacements 003

A small hole, drilled into the bottom of the bearing cover conveyed any seepage out of the bearing cover, through the hole and through a matching hole drilled through the backing plate. Now, any seepage automatically and easily would be conveyed away from the drum and brake shoe surfaces. Ingenious engineering!

#7 RearAxleMaintenance 007

Here’s what to do when servicing a rear axle. I’m not going to cover the entire procedure—just the bearing cover and installation of the slinger washer and the seal and its installation onto the axle prior to bolting the cover onto the housing.

Clean the bearing cover well. Leave no debris inside. I also clean the outside assiduously! I want no dirt put back into the workings. Clean the weep hole in the backing plate. We want any subsequent seepage to have a clear path out of the wheel.

Now, it’s time to install that slinger washer. Just drop it into the recess. No fuss—no muss.

Rear VW Axle Maintenance

Next, install the seal. If you have a seal installing tool, or a press, all the better. Otherwise, you can use a ball peen hammer and a block of smooth metal or even a block of wood. You may need to go round and round using a flat punch to finally seat the seal. Look from the outer side to see into the cover to be sure that the seal has seated all the way around.

#2 replacements 001

#9 RearAxleMaintenance 009

At this point, install the components onto the housing and axle. Note: the thin metal washer which comes in the new seal packet is NOT the oil slinger. It is a thin, tinned piece of metal which serves an entirely distinct purpose. (A Tip: If this thin washer in your packet has sharp edges from the factory stamping, use a small file to smooth those edges)

Install everything in reverse order (hopefully, you kept a record of how things were installed before you uninstalled them). But, wait….

Before installing the wide, outer spacer, we want to use our new-found knowledge. This is the “trick” which we want to employ.

We are going to install the spacer into the bearing cover BEFORE we install the cover. By carefully pushing this spacer into the seal, we are going to avoid pinching the lip of the seal or otherwise damaging it when the cover is slipped over the axle. You may lightly oil or grease the outer diameter of the spacer so that it will easily push into the seal opening. Be sure to have the beveled end of the spacer pointing towards the bearing—that’s where the small O-ring will seat.


#3 replacements 002

Now…carefully push the bearing cover, spacer and all, onto the axle. It will slide on smoothly without ever touching the lip of the seal. Bolt up the bearing cover.

It’s time to install the drum and the axle nut. Hand-tighten the nut—then use a tool to further seat the nut.

Lower the car and finalize the torqueing of that axle nut—to at least 217 foot pounds. Do NOT attempt to torque the axle nut with the car on stands. The torqueing process will throw the car off the stands! And remember, a poorly torqued axle nut will result in tranny oil seepage—the least of your worries. It will also allow the drum to wobble on the axle. This eventually allows the hardened steel axle to eat away the soft, cast iron drum splines resulting in a “spun hub”. Worse—the nut could loosen sufficiently to allow the entire wheel to fly off the axle. So do your best work here.

When the nut has been torqued, install a new cotter key. If you cannot find the cotter key opening, do not loosen the nut to find the hole. Instead, further torque the nut until the cotter key hole appears.

Some time after I learned of this maneuver, a VW friend called me—frustration evident in his voice. He had installed seals 3 times on his rear axles and each had leaked in short order. I explained the safety procedure. The next time we talked, he told me that he’d had no further problems with leaking seals.

Knowledge is a great thing when properly directed!

Happy Motoring!

Photography: Neva Salser

Posted by Jay Salser

My wife, Neva, and I have been driving and working on VWs since 1976. In fact, we raised our family in these cars. Now, we are retired and enjoy VWs as a hobby. The ’67 Beetle always has been our favorite year. We own a '67 Beetle and a '68 Karmann Ghia.

  1. Richard A. "Dick" Diaz August 28, 2014 at 8:12 pm

    Very timely article Jay! As you know I am experiencing this exact problem! I will print and add to my technical notes! I am hoping that despite that my ’67 having been previously converted from drum to disk brakes that the repair is the same! I was not comfortable tackling this myself, but have my car into a “non-VW specific” mechanic! But, despite that, he has a lot of experience with VW’s! This article will help me understand what he did, or didn’t do, for the repair! Thanks again for such valuable sharing of information with the rest of us! Dick

    1. Hello, Dick…It’s good to hear from you. After you and I recently communicated about your rear axle situation and the mechanic told you about the “double seal”–I got to thinking. Each axle kit comes with two paper gaskets. I wonder if the mechanic had used both of these paper gaskets between the bearing cover and the housing. If so, that could create a situation that might result in leakage. The second gasket is for the backside of the backing plate. However, almost no one goes to the trouble of removing the backing plate to replace that gasket. So, that extra gasket can just go into the “spares box”. I hope that your problem is soon resolved, Dick. jay

  2. I want to thank our daughter for coming to our rescue. Janeva Sulman has a nice camera and the skills required to capture the necessary photograph for the introduction. Both my wife, Neva, and Janeva enjoy contributing to the efforts at jay

    1. Yes! I should have mentioned. Thanks to all involved. Another great article for the world to enjoy. Dr. Salser runs things around here..

  3. I very much enjoy the way you write all your helpfull, and invaluable tech tips. All of which has bin saved, and tored for future use. if not imediatly put to use. A bit of well written humor always helps the info soak into the spare brain storage areas… You know, the place in the brain that some would want you to keep that grocery list, date and times for dinners with neighbors, and taking out the garbage… Lol
    Thanks for the great step by step, and Neva’s amassing photography.

    1. Dick–What we experience, we can record for others to enjoy. I really enjoy reading what you Readers contribute. My understanding of ’67s and of the World ’67 Community has expanded greatly through this WebSite. I never dreamed that the ’67 Beetle was so pervasive and revered! Each of us is taking care of our particular ’67 “turf” and contributing to the whole. Have a great weekend, Dick! jay

  4. Jay, thank you, your wife & daughter for a great article. This website gets better every day!!!!

    1. Hello, Sam…its the Readers who make GO! Sam–Readers, like yourself, turn into contributors. Let’s hear YOUR ’67 Beetle story! jay

    2. Sam,
      Thanks for following our efforts!

  5. …after two attempts, I’m taking my FAKE PORCHA to a real mechanic and let him practice a while. HOWEVEVER, with your data, I think I might actually succeed at this task.

    1. Hello, Meade…I am sorry that you have encountered a problem with the rear axle of your Porsche. Sigh! I hope that you ARE able to finally succeed! Maybe your mechanic has an hydraulic press. This makes the seal installation go better and very quickly. Thank you for reading and commenting here on jay

  6. I just recently bought a 1967 Beetle that was in excellent shape and has been converted into a Baja Bug fixing to change the LR rear axle seal.. thank you for your post! And look forward to more advice in the future..
    Sincerely Mike Gilbert

  7. Hi could someone please tell me what kind of oil I need for my 1970 vw beetles rear axle thank you cheers Arnie.

  8. Hello, Arnold…With your 1970 Beetle, you have a completely distinct type of rear axle–called
    Independent Rear Suspension (IRS), using CV Joints. Each CV Joint is sealed and has been packed with special grease to lubricate the internals of the CV Joint for years. These CV Joints can be serviced by a shop. It is sort of a nasty job! I think that most mechanics choose to buy the half axles and install them rather than to service the used axles. If you suspect faulty CV Joints, have the vehicle examined by a qualified vintage VW shop. jay salser

  9. Nice read but I’ve never used the oil slingers and never had a leak.

    1. Hello, Arthur…consider yourself lucky. At some point, the Seal Lip will wear sufficiently so that transmission oil will begin to seep into the cavity behind it. Fortunately, the Bearing Covers for ’67 have the weep holes which allow for tranny oil to creep out the Backing Plate where it slings off into “space” and then drips onto the parking place when the car isn’t moving. Without the Slinger in place, oil will creep out of the Bearing Cover and onto the Brake Shoes–ruining the lining and adversely affecting the braking ability of the car. I encourage you to install the Slingers the next time you need to do a Seal replacement. Maybe you should have your Tranny Oil Level checked–if the oil is low, not much oil is running into the Axle Tubes to lubricate the Bearings. And, thus, you might not have seepage out the Backing Plates due to lack of oil in the Tubes. jay salser

      1. Yes eventually it will but what caught my eye on your article was that your seal started leaking again soon after.
        The oil slinger has nothing to do with stopping the seal from leaking. It will either leak or it won’t. The slinger prevents the oil from getting on the brake pads and that’s it.

        Your seal leaked after you put in in for other reasons than the slinger.

        Enjoy your day

        1. Correct….the Slinger only helps to divert the seeping oil to the Backing Plate. The force of the article was how to install the Seal without damaging the Lip of the Seal. The Slinger is mentioned because it is an integral element in the process. jay

          1. My mistake if I read it wrong. Thought you were saying that the seal leaked because it didn’t have the slinger. Lol.
            My bad.

            I usually end up destroying the seal on VWs. Which is why I pay a guy 20 bucks to do it

  10. Arthur–it’s okay. I like to document all of the parts of an operation while I’m there. The Slinger was a part which changed the history of Rear Axle Sealing–so I wanted it to have adequate coverage. BTW–I have found a Seal Kit which contains a brand New Oil Slinger! I am so happy to know that once again we can obtain this formerly hart-to-obtain-part. Keep enjoying your VW, Arthur! jay

    1. I do have a question on brake shoes if you could be so kind as to help me out.
      The VW I have is a Meyers Manx.
      (Yes an original)
      I have the Swingaxle as I stated but I’m having problems with my brake shoes.
      I bought new ones and unfortunately threw away the old ones.
      My problem is they don’t fit.
      They are 1- 1/2 inches wide and get caught up on the hole bump on backing plate where the e brake cable comes in. They won’t line up with the spring hold hole and fit in the star adjuster . looks like they are too wide.
      Are all backing plates with weep holes the same?
      Thanks Arthur

  11. I say in the Article that the steel Slinger Washers no longer are available. I have begun to find them in some kits. If yours is damaged, check all available kits to see which one might have a replacement Slinger Washer. jay

  12. Hello. I am working on a VW Bus 1966 and replacing the rear seals. The bus did not have the slinger when I replaced the axle seals and with the new seals they are still leaking. Do you think it is because I did not use the slinger? Thanks for the article.

Comments are closed.

%d bloggers like this: