Retrofitting Type 3 Drum Brakes
(on your VW Bug)

Firstly, you will need to get the complete rear brake assemblies from a Type III. These should be readily available at the wreckers and they might even cut them off with a torch for you (leaving it up to you to disassemble them at home). Mine came this way, complete with outer CV joints and parts of the trailing arms and spring plates. Now, now... don't get upset... I didn't have a choice. I simply told a local garage (that specialized in air-cooled VWs) what I wanted and he cut them off and had them waiting for me when I arrived. Anyway, the complete assemblies cost me $100 CAN (no taxes).

While you are disassembling everything, this would be a good time to decide what can stay and what needs to be replaced. I replaced literally everything that could physically wear out, since I didn't believe in putting old brake parts on a car that already had brand new disc brakes up front, as well as a new master cylinder, new steel lines, and new stainless steel flexible brake hoses. New shoes were a must in my situation, but should still be considered, nonetheless (be sure to have the drums turned as well). If one wheel cylinder is bad replace them both, since they often fail one right after the other (this is doubly important when it comes to used parts and you don't want a leaky wheel cylinder to saturate your new brake linings after only 1,000 miles of driving). Spring hardware kits don't cost that much and brakes can produce a lot of heat - enough to weaken these components over time (as will rust) and cause the shoes to drag and not adjust up properly. Check the wear points on the backing plates where the shoes contact to make sure that there are no deep grooves that might cause the shoes to hang up (welding them up and grind them flush if necessary). Finally, make sure that you save your old axle bearing covers since the new ones may not fit properly. Sandblasting & painting everything is optional, of course, but it does make for a cleaner installation afterwards.

Jack up your car, remove the rear wheels & drums, and apply some penetrating oil to the brake line fittings at each wheel cylinder. Measure through the center of your old Beetle drums the precise length of the axle splines. Do the same for each of the new Type III hubs. You must then find a machine shop that can remove the extra material from the outer snout of each hub so that when installed, the slots in the castle nut have enough room to clear the cotter pins (accuracy isn't critical, but it should be close).

Begin by clamping off the flexible brake lines connecting the axle to the body so that brake fluid will not drip continuously beneath your work area. Using a quality line wrench, see if you can get the brake line fittings to move. If necessary, use a torch to heat up the threaded portion of the wheel cylinder (clean up any excess penetrating oil first and make sure you keep the flame away from the actual brake line). If it still doesn't want to move, you could use a pair of Vice Grips^TM to grip the nut tightly (although you really should replace the line at this point).

Remove the shoes and make sure that the emergency brake cables move freely (replace them if they don't). Check the star wheel adjusters and determine if they need to be replaced or not (it helps if these operate smoothly so that you can adjust your brakes easier). Clean up any brake hardware you intend on reusing and set it aside. Remove the four bolts that hold the axle bearing cover on and gently tap around the back of the backing plate to break it free (you might want to place a tray or a couple of rags to catch any leakage). There should be remnants of the old cover o-ring visible on either the backing plate or the cover itself. Likewise, there should be a small o-ring on the axle shaft, as well as a steel spacer and a thin washer. Finally, remove the backing plate and examine the outer axle bearing (now would be a good time to replace them if they show evidence of wear or corrosion). Replacing the actual bearing requires a special puller and is beyond the scope of this article.

Clean up the new backing plates and check to see if the spring tabs which follow the star wheel adjusters are intact. If not, new ones should be fabricated or you risk your brakes going out of adjustment (due to that fact that nothing will be preventing the adjusters from turning). Test fit the new backing plates with your old axle bearing covers. The backing plates should fit firmly and not move at all when the four mounting bolts are tightened down. Each axle seal kit should come with one shaft seal and two paper gaskets, as well as two rubber o-rings. The large o-ring fits between the axle tube flange and the backing plate and is a crush fit. If the o-ring does not allow the cover to fit flush against the backing plate, you can use RTV or a good automotive silicone sealing compound to substitute for the o-ring. Many people also like to use silicone instead of the paper gaskets but this has always been a personal decision since both seem to seal equally well. You might also want to take advantage of the unobstructed view to do a visual check on your tranny, axle boots, clutch cable, etc. at this time.

So now you've got a bunch of parts sitting around in various places... now what? Extract the old shaft seals from the axle bearing covers and install the new ones, using a hammer and a flat piece of wood to drive the new seals in squarely (number-side up, open side facing down). A little bit of RTV or silicone can be applied around the outside of the seal where it contacts the cover prior to installation, but this isn't absolutely necessary. Afterwards, check that the small tension spring in the inside of each axle seal has not come loose while you hammered in the seals. Using a brass drift and a gentle tapping action, install the new axle bearings (optional; sealed side towards the center of the car). Next, install the large o-rings around the outer race of the bearings and smear them liberally with a few drops of oil. Install the new backing plates, using one of the paper gaskets between the axle tube flange and the backing plate. Next install the washers, followed by the small o-rings (lube these as well). Install the spacer and tighten down the four bearing cover bolts to 40 ft-lbs, remembering to install a paper gasket between the backing plate and the cover. Make sure that the lip of the axle seal rides smoothly on the axle shaft and is not nicked by the splines. Now refill the transmission to the proper level and check your work. There should be no signs of leaking.