Rear End Sag Correction

by Josh Rodgers


The following procedure is a step by step on how to correct the rear ride heighth on '68 - '79 IRS buses.

PREFACE:

The time involved varies, of course, but I was able to do the procedure in approximately 5 hours (3.5hrs on the first - learning, 1.5 on the second side - rushing and making stupid mistakes ) without any step by step instructions. I feel with these instructions a person with a good set of tools and a minimal amount of mechanical ability could complete the procedure in appoximately 3 hours. One person could complete the job but I would highly recommend a second person (my procedure includes disconnecting the brake lines which is optional but I recommend it, so you will need a second person to help bleed the brakes when you are done).

TOOLS NEEDED:

(A) Open/box end wrenches: 11mm, 16mm, 17mm, 18mm (or 3/4), 22mm (or 7/8)

(B) Ratchet with sockets: 16mm, 3/4" (19mm?), 22mm

(C) Jack stands (2)

(D) Large hammer

(E) Pry bar and/or Small wedge

(F) Small flat-head screwdriver

(G) Floor jack

(H) 6mm Allen wrench or triple square wrench, depending on your CV bolts

(I) Good Vice-grips

(J) Protractor

Additionally, I would like to add some optional tools that I used that really made the job easier, but are not necessary.

(A) 3/4 inch drive Air or Electric Impact (an electric impact is one of the best investmensts I have made for old Vw's)

(B) Large floor jack

(C) I presoaked all bolts thoroughly with Liquid Wrench (or similar lubricant).

(D) I want to double-emphasize the word GOOD on the vice-grips, without worn jaws

(E) Brake Fluid

PROCEDURE:

  • (A) Begin by breaking the lug nuts on both rear wheels to easy removal when tires are off the ground.

  • (B) Block the front tires so the vehicle can not roll forwards or backwards on you and jack the back of the vehicle up at least high enough to remove the rear wheels

  • (C) I placed large jack stands under the rear main frame supports just forward of the torsion housing.

  • (D) I then removed the floor jack and rear wheels.

  • (E) Remove the lower shock mount bolt (mine had 17mm on one end and 3/4" (19mm?)

  • (F) Next, I removed the outer CV bolts (the trick here is to dowse the bolts ahead of time with lubricant, then take your vise-grips and try turning the bolts forwards and back, tightening and loosening until they break, then use your Metric Allen wrench or triple square wrench). I used something to support the axles to keep em from dropping to the floor. Important: If dirt gets in the greased ends of the CV's or if you are low on grease, your CV's may pop when reassembled. Now is a good time to regrease. Use special CV grease rather than standard grease. Also, I covered the ends of the greased CV's with Zip-lock bags (or Duct tape) to keep dirt out and grease in.

  • (G) I disconnected the brake line that runs thru the hub. I will say this is optional but the first side I did was hard to get a part until I disconnected so it is one of those things where if you go thru a little extra work now, it will save you much time and head aches later. This is NOT necessary on the Type 1.

  • (H) Next, I removed the bolts (2 small, 2 large -> 22mm?) from the outer hub that run thru the spring plate. This is where the electric (or air) impact showed its worth.

  • (I) Now, you should just have bare spring plates with nothing attached to them.

  • (J) At this point, we take the four bolts out of the torsion housing ends (16mm?) and remove the covers. A black rubber spring plate bushing should come out with the cover.

    [Editor's Note: There are two of these bushings, one on either side of the spring plate. Now is a good time to replace them with new ones. The part number is 211 511 245A for '50-'79 Type 2s. You'll need 4--they cost around $7 each (1999 prices). Lubricate them with talcum powder (not grease!) before installing. Talcum powder is available from your local pharmacist/chemist. FYI: A Porsche aftermarket company selling torsion bars states that breakage of the bars is not covered under warranty if they were not installed with all new spring plate bushings. Installing only new outer bushings is not acceptible--you must replace all four together.]

  • (K) This is where I marked the current location of the spring plate on the splines of the torsion. I just scratched an arrow on the spring plate that pointed to the center of the little circle on the torsion housing but, in retrospect, wish I would have scratched a full line to go all the way across the torsion bar and spring plate.

  • (L) Now great caution must be taken not to pull the torsion bar from its spline location on the inside of the torsion housing (the torsion bar is not secure on the inside; it is just splined on both ends; there is one torsion bar per side). I also scratched a line into the torsion housing using the spring plate as a straight edge just in case this happened. Again, tons of lubricant was applied to the spline area of the spring plate and torsion bar.

  • (M) What we want to do now is push the torsion bar thru the eye of the spring plate. I did this by hammering a wedge or crow bar behind the spring plate, and hammering a deep well socket thru the center of the spring plate on the torsion bar (wedge pushes spring plate out, socket keeps torsion pushed in). Take your time and be aware of what you are beating on. A small hammer worked fine for me. If the inside of the torsion bar pops out, don't freak out, just realign the spring plate with the mark we straight-edged on the torsion housing.

    [Editor's Note: If you scratch any paint of the torsion bar, it is a good idea to clean and paint so no rust occurs. Rust will eventually cause the bar to break as it penetrates the bar, so use precautions].

  • (N) More Liquid wrench...Heat????? Have you taken a break yet????? Give it a couple seconds and come back with a little more patience and possibly a new perspective.

  • (O) OK...now that we got those off, Now comes the time for precision.

  • (P) See George Lyle's procedure for proper adjustment of the torsion bar to attain the correct ride height.

  • (Q) Now that your adjustment is done, more than likely, you will need an assistant here to help you get the spring plate up above the step on the bottom of the torsion housing cover. I used a large floor jack to jack the spring plate up so far, then hammer it on at the same time.

    For reference, when I jacked up the spring plate, after a while, it did eventually lift the bus off of the jack stands.

  • (R) Also, the torsion housing cover can be kind of tricky to get back on. Don't forget to install the spring plate bushings lubricated with talcum powder. I took a long skinny bolt and washer through one of the bolt holes and the cover that would allow the cover to move around a little, then got one of the original bolts started and then got the other two originals in. Once I got those pretty snug, I removed the unoriginal long, skinny bolt and nut and replaced it with the last of the original bolts.

  • (S) The rest is basically everything in the opposite order. Put brake line and outer hub back on. The CV and the shock are bolted back to the wheel hub and you reattach the tires.

  • (T) Don't forget to bleed the brakes if you did disconnect the brake lines.

  • (U) Finally, to insure proper tire wear and stability, take your baby by your local Tire guy for rear wheel alignment check.

  • (V) Don't forget to re-aim those headlights!

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