Shaking under Braking 65 SC

[elise111]

I'm happy to report a recent purchase of a 65 SC after a long year of looking. Thanks to this forum I'm learning about these old VW's quickly. One problem I'm troubleshooting now is with the brakes.

When braking above 50mph, the whole truck tends to shake. The steering wheel doesn't shimmy when this happens, so I've focused on the rear brakes. Rear bearings feel good, pads are relatively new, and I've replaced all 4 shocks recently.

Questions for folks that may have been through this in the past:
1. Since the steering is not a modern rack and pinion design, will it still shimmy if the problem was with the front wheels?
2. The rear drums are both significantly oversize in diameter- one by 2mm, one by 5mm. Not good, but the worst out of round measurement was only 0.08mm (about 0.003in) with a simple CMM-type inspection. This didn't seem like enough out of roundness to be significant, but I do notice that when adjusting the shoes I don't get consistent, 360deg of dragging, perhaps indicating a out of round condition?

Cheers,
Pete

[NAES]

Remember the front brakes do about 70% of the work so I would look there first at the drums. Get them turned if they're out of round.

Is the shimmy a side to side movement of the bus or a pulsing in the pedals?

Side to side is more than likely worn steering components. Steering box, drag link, center pin, tie rods, link pins, king pins, front wheel bearings. All of these can contribute to a large problem if each has just a few mm of slop.

Pulsating in the pedal is usually an out of round drum.

HTH
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Barndoor Mafia
Box On Wheels
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[campingbox]

More than likely the front drums are out of round. Have a machine shop check them and if they turn them have them arc the brake shoes to match the drums.

[Clara]

also replace all 4 of the rubber brake flex lines if they are more than 5 years old.

I had one that was going bad and it would make the bus shimmy when braking.
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