Beetle Z-Bar

Jay Salser does it again, folks. Many many ’67 Beetle owners around the world appreciate the fruits of your labor. – ES

At some point, I accumulated some Z-Bar (Equalizer Spring) Components. I decided to sort these and at least learn their Names and Part Numbers. There’s not much future in calling parts—“the thing-a-ma-jig”. You get the picture.

I know that a lot of 1967 Owners won’t be excited by all of this, but there are some who enjoy knowing about the “minutia” of their cars. For those—I decided to post the information which I have accumulated. Thanks to David Brown, I have been able to acquire those VW Part Numbers which I could not find on my own. And, Neva Salser whipped out her Digital and snapped a multitude of photos from which to choose some for this exercise.

Note: The Z-Bar continued into the 1968 Production Year for 1968 Beetles so that the Z-Bar is not a one-year-only part.

In Europe, the Z-Bar took a different configuration. Also, somewhere in there, the replacement for the Z-Bar with which we are familiar was superceded by the one in the photo below.

But, first, a bit of explanation about the Z-Bar. Some confusion reigns over the purposes of the Z-Bar. Let’s see what VW says about the Z-Bar Function.

From Bentley’s Official Service Manual (’66-’69—Blue Manual)

Transmission and Rear Axle, Page 70, Section 11, Equalizer Springs:

“The purpose of the equalizer is to produce an additional progressive spring action to assist the torsion bars when under load. Because the operating levers slant in opposite directions, the action of the equalizer spring does not affect body roll, and the front axle assembly is there-by enabled to absorb more roll to give better cornering of the vehicle.”

Thinking of this definition–of interest to me were the differences between the two Levers (right and left). The Left Lever (driver’s side) has a casting mark “L”. The Right Lever has no such casting mark.

The two Levers are distinctive as to configuration. This, at a casual glance, may go unnoticed. However, when the two Levers are placed side by side, the difference becomes immediately apparent.

It also is important as to the direction each Lever fits onto the Cross Rod (also called the Main Stem). I have included two photos of a Lever—showing the side which faces the center of the car and the side which faces the outside of the car. I examined more than one Z-Bar to assess this installation factor.

As well, the Left Lever is fitted onto the end of the Cross Rod which is marked with the VW Logo. Again, I checked to verify this. The pointed Grub Screw (Set Screw) positions, coupled with the different physical characteristics between the two Levers, cause the installed angle of the Levers to differ. This gives the Z-Bar its compensating property. Sort of an “anti-twisting” property.

The Grub Screw (Set Screw) is marked KAMAX with the hardness factor 8.8. The Grub Screw is accompanied by a 13mm Hex Nut with no markings. The Nut serves to lock the Grub Screw once the Grub Screw has been screwed through the Lever and into the conical recess in the Cross Rod. The Grub Screw has an Allen Head which requires a 6mm wrench. 

The Cross Rod (Main Stem) is fitted with a cylindrical Rubber Bumper, positioned approximately at mid point on the Cross Rod. The purpose of this Bumper is to cushion any contact which the Cross Rod might make with the underside of the car. The Bumper is approximately 4 ctms long by 6mm wall thickness with an outside diameter of approximately 23mm and an inner diameter of approximately 14mm. Given the nature of this split Bumper, the OD and ID can vary when installed (opens more or closes more). Unfortunately, this Rubber Bumper no longer is being produced.

The Cross Rod is approximately 38-6/8ths inches in length and 12mm in diameter.

Missing, also, from refurbishing kits, are the Rubber Caps (113-501-549) and the Hard Rubber Washers (113-501-849)

Maybe someone will step up to the plate to reproduce these items which are integral to the condition and operation of the Z-Bar.

The following are additional photos of Z-Bar parts.

Z-Bar Components With Part Numbers:

  • 1. Levers—(casting letters/numerals not relevant)
  •      —- Left—Marked L for Left (Driver’s Side)—113-501-845
  •      —- Right—Unmarked for Right (Passenger’s Side)—113-501-846
  • 2. Lever Grub Screws (X2)—Use 6mm Allen Wrench—KAMAX, 8.8 Hardness, 8mm x 1.0—N-014-727-1
  • 3. Lever Set Screw Lock Nuts (X2)—13mm X 8mm x 1.0—N-011-152-1
  • 4. Lower Rubber Operating Rod Bumper (X2)—VW Logo-113-501-737 (by HS)
  • 5. Lower and Upper Operating Rod Threads (X4)—8mm x 1.25
  • 4. Lower Operating Rod Steel Washer (X2)—ID-8.8mm—OD-29-30mm—361-501-575
  • 5. Upper and Lower Operating Rod Self-Locking Nuts (X4)—14mm X 8mm x 1.25 X—113-415-431
  • 6. Lower Rubber Guides (X2)—(grommets for #s 8-9)–113-501-753
  • 7. Operating Rod Rubber Caps (X2)—(Weather Resistant Caps)–113-501-549
  • 8. Axle Tube Guide/Support (1)—right—(mounting cup)—113-501-840
  • 9. Axle Tube Guide/Support (1)—left—(mounting cup)—113-501-839
  • (Bolts (X4) and Lock Washers (X4)—(for mounting cups #s 8-9)—Bolts are 38mm instead of 35mm—N-010-138-1/Washers for same are N-012-012-2/Nuts for same are
  • 10. Lever Damping Bushings (X4)—113-501-835
  • 11. Upper Short Plastic Guide Tube/Sleeve on Operating Rod (X2)—113-501-832
  • 12. Lower Long Plastic Guide Tube/Sleeve on Operating Rod (X2)—113-501-831
  • 13.Cross Rod-(called the Main Stem)—113-501-819—Part # deleted as of Oct., 1969 (approximately 38-6/8ths inches in length)
  • 14. Cross Rod Center Rubber Bumper—113-501-815
  • 15. Steel Outer End Caps-Right or Left (X2)—113-501-811
  • 16. Steel Inner Caps-Right or Left (X2)—(with hole in the end for Cross Rod)—113-501-809
  • 17. Conical Bushings for Cross Rod (X2)—113-501-813
  • 18. Operating Rod Top Plate (X2)—113-501-825
  • 19. Rods (Torsion Bars)—113-501-805
  • 20. Left-Driver’s Operating Rod—(long upper section)
  • 21. Right-Passenger’s Operating Rod—(short upper section)
  • 22. Hard Rubber Washer (called Washer–between Lever and the Inner Cross Rod Bushing Cover)—113-501-849

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. That is wonderful Thank you Jay!
    We have had several 67’s with different configs. One had a leaf spring under the rear axles called a (sway-a-way) as a anti-sway device presumably. The other had a z bar and on the third car it was removed because the previous owner said it made a clunking sound. The sway-a-way did seem to produce less oversteer which was nice but it was always engaged where the z bar only came into play when needed. The Z-Bar car’s ride was the best of all three, especially when cornering. The z-bar was another intelligent design by those German engineers.

    1. Hello, Russ…It’s good to hear from you! VW “experimented” with the Z-Bar for a couple of years and apparently it proved not to be so effective as to keep it. There is a lot of discussion on the issue. The concept is pure! Apparently it just did not do what the VW engineers envisioned. Enough so that they didn’t want to spend more money on it. That said–I’m not removing my Z-Bar! The thing which occurred to me was that this fairly simple part of our ’67 Beetles turned out to be far more complicated than one would think at first glance. Hey–keep loving your ’67, Russ! jay

      1. Jay, enjoyed the article. I found it very interesting in that I am currently working on a 68 convertible that originally had a Z-Bar suspension, optimum word being originally. The previous owner removed it. I am putting it back in. I have a couple of questions if you (or anyone else) have the time. First off, I believe I have all the parts except one of the linkage rods, I believe I am missing the passenger side, the one I have was attached to the “flat arm”, it is approximately 12″ long. The distance from the large washer to the end of the bottom nut is approximately 6″, the space between the large and small washer is approximately 4″ and the distance from the small washer to the top nut is about 2″. I read on another thread that the passenger rod is 10″ overall length. Can you confirm? Also what is the spacing between the points as I have mentioned above. Thank You for your time and patience. — Jim

        1. Hello, James—I had not realized that you also had commented to me under this Article. I did some measuring. But–please refer to my article (above) in photo #12 which compares the driver’s side (left) with the passenger’s side (right) Operating Rods (in the photo, the left side of the photo is the driver’s side and the right side of the photo is the passenger’s side). Then, look at the Parts Numbers and Descriptions #20 and #21. The Upper Section of the Driver’s Operating Rod measures about 4 inches while the Passenger’s side Operating Rod Upper Section measures about 2-1/2 inches. If this is unclear–please contact me again. I will be more than happy to help any way that I can, James. jay

      2. If I had to guess, the reason they discontinued it was due to the incoming IRS rear suspension for the 1969 model year. That, more than likely, negated the use of such an addition. Purely speculation on my part, but VW would never keep something that complex and costly if it was not needed.

    2. Russ…I should have added that for 1969 Beetles destined for USA consumption, a completely new rear axle was designed–the jointed axle without a tube. The Z-Bar came suddenly and left almost as quickly. Maybe it was an “experiment” which came too late to be greatly appreciated and/or perfected. Perhaps just the longer axle for ’67-’68 would have been sufficient until the CV jointed axle was introduced in ’69.
      Let’s you and I take a time-machine ride back to peer into the workshop of those engineers who squinted at late-night drawings over warm German beer. Maybe we would have a lot of our questions answered if we were afforded that luxury. jay

      1. The true IRS of the 69 was the right answer. The swing axle, which is much better than a solid rear axle, had it’s limits and the Z-Bar an improvement. What’s really amazing is the VW’s cousin the Porsche. If you want to see rear engine suspension taken to it’s zenith look at the development of the 911. There’s more linkage, compensators, anti-sway, dampener madness going on there, than in any other contraption ever created.

  2. A++++++++++++++, Jay!

  3. Photo #13: Axle tube support cups. I picked up a box of spare parts from a guy a couple of years and in that box were a set of these support cups, left and right (they are asymmetrical and slightly different, left to right). I just recently found out what they were!! In the spirit of the VW family, free to anyone who wants to pay the postage from here to there. Send me message.

    1. How neat, Dave! That’s in the spirit of the 1967 Beetle Community. Thanks for your very kind offer! jay

  4. Stephen M Jaeger March 9, 2017 at 3:20 pm

    I love my Z bar! I dutifully repainted everything and replaced what I could (no new caps available though.) But does it actually do anything? I don’t know. It certainly doesn’t handle like my BMW on a tight turn. But I guess it drives like a 67 bug.

  5. “But I guess it drives like a 67 bug.” (Laughing)

  6. Roland Waller March 9, 2017 at 5:13 pm


    1. Hi, Roland…Isn’t it fun! Learning about our Vintage ’67 Beetles is a journey that often leads us into some strange pathways–but always–leads us to great friendships! Keep enjoying your ’67, Roland! jay

  7. David Brown of Pennsylvania comments: ” …a couple of additions for your interest. The VW Parts Book puts the change-over to the newer style Down Links and Arms at Chassis # 119 381 000 which appears to be around November/ December of 1968. Parts Book Supplement # 13/68 introduces the new Operating Rods, and the new Arms (113 501 833 ) are now the same Left and Right. When the new style came out, all of the former applicable bits were deleted and no longer produced, making NOS early stuff pretty hard to find. I was surprised that you were able to come up with a Photo of the new style Z-Bar Parts !! David” (Thank you for this additional information, David! jay salser)

  8. Fantastic Jay for you to bring this information forward. Great for our little select community

    1. Good morning, Jeffrey–I don’t believe that I’ve had the pleasure of “talking” previously with you. It’s always good to hear from more great 1967 Beetle Owners! I think that all of us want to talk about the facets of our Cars–Eric and Amanda Shoemaker have made this possible in the very best manner. Thank you for taking time to chime in–we’d love to hear from you more often! jay

  9. “Great for our little select community.” :-)

  10. Z-Bar Reasoning

    In 1967, VW introduced the Equalizer Spring. It continued for the Deluxe Beetle which came to the USA Dealerships for Production Years 1967-1968. For Production Year 1969, the CV Jointed Axles were introduced.

    For years ’67-’68, the Torsion Bar was reduced from 22mm to 21mm. This “softened” the rear suspension.

    At the same time, VW introduced the “Long” Axle—widening the Rear Track.

    The Equalizer Spring, in one sense, compensated for the new 21mm Torsion Bars, functioning as an “Auxiliary Torsion Bar”, or an “over-load” spring.

    With the rear of the car unburdened by passengers or weight, the Equalizer Spring is passive. The Equalizer Bar begins to function only when enough weight is introduced to remove/reduce the pre-travel from the Operating Rods.

    If the rear of the car is weighted enough to remove/reduce the pre-travel from the Operating Rods, the Equalizer Spring becomes a “helper” to the Torsion Bars. In such a case, with the car driving straight ahead, or even starting from a standing position, the Equalizer Spring acts as an auxiliary spring, effectively increasing the spring tension on the rear wheels. This allows a softer ride during normal operation but provides additional spring tension when necessary (holding both rear wheels firmly and evenly to the pavement).

    When a vehicle is cornered hard, the inside rear wheel tends to “unload”—it may even leave the pavement. At the same time, body roll loads the outside rear wheel.

    The Equalizer Spring Lever on the outside wheel is pushed upwards by the relative movement of the outside wheel, relative to the body suspension. The design of the Equalizer Bar exerts downward action upon the opposite (inside) rear wheel. The idea is to equalize the pressure on both rear wheels to keep them both in contact with the roadway during the maneuver.

    The Z-Bar may have little to no effect on cornering unless there’s enough loading on the outside wheel to take up the pre-travel in the outside Operating Rod.

  11. Great article. I am in the process of doing mine. However, I can’t find the “rod cap” in any of the regular supplier catalogs. Can anyone help?

  12. I did not know what all that knocking noise was on My 67 Beetle. They look like some kind of shock. Would like to remove them to get rid of the knocking noise. Is this ok to do. I cannot tell that they are doing anything. Your thoughts?

  13. Great article and informative comments! Many thanks!

    1. Hello, Karl. Thank you for reading this article. It was an interesting “journey” to research and understand how the Z-Bar operates. Unfortunately, it was destined to the scrap heap by VW–apparently because, for the expense, there wasn’t enough return. Keep enjoying your ’67 Beetle! jay

  14. I’m completing a restoration of a ’67 that long ago had the Z-bar removed except for the cross rod and its mounts. I found used levers and operating rods and bought a Wolfburg Z-bar kit but was a loss as to which parts go where until I came across this great writeup. A few notes that might be of help to others:
    Your identification of the drive-side end of the cross bar with the VW logo and the side photos ID of the levers saved much trial and error.
    Bentley text has the long/short operating rods on the wrong sides. Thankfully, you added the proper side locations to your component ID list.
    The old, used operating rods had the plastic guide tube sleeves inside of the top dampening rings and the big rubber stops. The Wolfsburg kit sleeve only fits inside the top dampening rings but not the rubber stops. The stop ID is the rod OD so no space for the sleeve. I cut the sleeves to fit below the stops and hold them in position.
    Many thanks for the article!

  15. Natasha Branson November 1, 2020 at 6:17 am

    It might be interesting for people to know (and I’m not sure how original it is, but it looks pretty original) my 1982 Mexican beetle has Z bar too. Found this page while trying to figure out what it was. Thanks

    1. Thank you for entering the conversation, Natasha! Since is based in the USA, we have (mainly) the Deluxe German 1967 Beetles to study. Your comment is valuable in the Worldwide scheme of things. I believe that yours is the first comment about the Z-Bar on a Beetle other than the Deluxe ’67 Model. Is your set-up like the “original version” or modeled after the “european” model (I briefly touched upon a “second version”, apparently used mostly in Europe). jay

  16. Stephen Myers April 7, 2021 at 5:53 am

    Being the owner of a 1967 right hand drive UK Beetle I was delighted to find your article concerning the Z-bar installation. Needless to say, that mine disappeared many years ago and I failed to save the non-rusted, non-broken parts. I gather from your article that it is not a vital piece of equipment but wonder whether you have heard of anyone who happens to sell a complete set-up (european style). I can find no mention on the conventional suppliers’ sites.

    1. Hello, Stephen–and thank you for reading and commenting on this Article. Of course, only the Deluxe ’67-’68 Beetles came to the USA. As a result, it’s probably unlikely that one could locate the “european” version here. But, there should be plenty of
      those cars in Europe. I am going to respond to you via e-message a bit later today–so “stand-by, Stephen. Let’s see if we can engage someone on this subject. jay

  17. Armando Guzman Vega May 29, 2021 at 5:25 pm

    Hello Jay, loved the article about the Z bar. I have a question: my 67 project doesn’t have room to put the inner end caps that hold the long rod in place. I just removed the Z bar to clean and repaint it. The outer caps had the hole on them, as you can see in the pictures. In your article, the caps with the hole go inside the body. and the full caps go outside. The fixed studs point to the outside to install the caps. Any explanation for this?
    On another subject, I placed an ad in the for 2 Pierburg fuel pumps. unrestored but in good used conditions. If anybody is interested I would like to trade for a horn ring and button, mine is broken. Thank you

  18. Hello, Armando…Thank you for commenting! The outer caps cannot have a hole–they are covers to protect against dirt and moisture. The inner caps have the hole through which the cross rod extends to hold the bushing. Perhaps a previous owner worked with the assembly and just put them together backwards? But, maybe I am misunderstanding your comment because there would be no way to mount the rod if the caps with the holes were to be affixed to the two studs facing toward the exterior.
    Please correct me if I am wrong. jay

  19. Armando Guzman Vega May 30, 2021 at 10:57 pm

    Jay, thank you for your helping me trying to figure out how to correctly install the
    Z bar. I got my ’67 in pieces, as a puzzle, and the Z bar was installed incorrectly. Since our communications via e-mail, and with the help of pictures I was able to figure out the mystery of how the bar goes back in the car. In the Z bar article, picture # 16 shows the inner cups and the rubber bushings. The bushings are slanted to fit into the slant in the inner metal cups. In picture #16 the metal cups show a small “pimple” between the slanted cup and the stud hole. When you look carefully at the car body, in the driver’s side there is a corresponding “dimple” between the BOTTOM stud and the hole where the metal inner cup fits to hold the cross rod. Then you go to the passenger side and the “dimple” is between the TOP stud and the hole for the slanted cup. So Even thou the cups are not marked L or R, the dimple in the car body determines that the cup in the driver’s side goes in with the dimple in the bottom. and the passenger side goes in with the dimple on the top stud. I know that there hasn’t been any comments about the Z bar in the last 4 years, but I hope this will help people that want to have the Z bar installed correctly. I will send pictures via emai. Thanks

  20. This is a great explanation, Armando! VW arranged things to eliminate guess-work. I failed to note this feature in the article. I enjoy seeing the 1967 Beetle Community becoming involved as contributors to our communal knowledge! Keep us informed about the progress with your Beetle! jay

  21. The end caps are asymmetrical, which way to the go, I noticed though the WW kit the rubber bushings are not? Thank you

  22. Hello, Richard…I do not have my car on stand or jacks, so I was able to have limited viewing only of the two caps. I am guessing that you are talking about the outside caps–facing towards the tires (?). On the driver’s side, the “wide edge” faces the front of the car. Reverse this position for the passenger’s side. Since they are identical–VW apparently did not think ahead of us who have to learn by the seats of our pants! LOL

    1. Thank you Jay. I’m sure its not too important since the WW rubber pieces are not contoured like the originals.BTW the shorter spindle goes on the passenger side? correct?

      1. Correct, Richard–see #21 in the information section below the Article: 21. Right-Passenger’s Operating Rod—(short upper section)

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