Disc Brake Pistons for DIY Caliper Rebuild

[Bill Waite]

In the above photo, one set of "old" front pistons are on the right. On the left are brand new pistons.

After cleanup the old pistons show no surface wear or defects on the chromed sealing surface. With careful measurement using a micrometer screw gauge, all of the pistons (new and old) measure in a range from 48.01 to 48.04 mm. Is there any compelling reason that I shouldn't reuse the existing set? If not, I'll likely have a brand new set of front and back pistons for sale in the classifieds at a favorable discount!

[Greg Bryan]

Bill - I reused the pistons in my C that were in similarly good shape and they have been fine for the 8500 miles I've put on the car so far.

[Peter Bartelli]

Using 911S aluminum calipers on your 356?

[Bill Waite]

Thanks, Greg... that's what I was hoping to hear.

Using 911S aluminum calipers on your 356?

No... rebuilding the old ones. Found the article in the "Resources" section to be very helpful:

https://porsche356registry.org/article/153