Like the clutch master and slave cylinders, I doubt that there is really
concrete evidence that both wheel cylinders tend to out at the same
time.  But I haven't researched the archives on this one.  Given how old
these vans are, it certainly isn't a bad idea to replace both if you
know it hasn't been done ever or a long time ago.

I had one cylinder go out 15k miles and over a 18 months ago on my 85
Weekender with 200k miles and the other one is still going strong.
Brakes are really firm.  And, being lazy and postponing hard work, I
only bled the right rear after changing that cylinder.  Didn't pressure
bleed it, just used a few pedal pumps from my son and gravity.   I know
that isn't the best practice, but it has worked.  At that time it was
not yet two years since the brakes had been bled by the PO's shop.

All that said, I plan to do both cylinders on my Syncro soon as it needs
bleeding and the wheel cylinder job itself is easier than the bleeding
part to me.

Sam

--
Sam Walters
Baltimore, MD

89 Syncro GL, Zetec Inside
85 Westy Weekender
85 Mercedes Benz 300D Turbodiesel - to become veggie oil powered

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