I finally got my brake cylinders in the mail for my Studebaker. I changing my wimpy Champion front brakes for '51 V8 Commander drums. My local NAPA didn't list cylinders for these brakes so I got into the trusty ol' interchange manual and found that the Late-'54 to '56 Studebaker trucks use the same cylinders, which NAPA did show as able to order. Anyway, the housings and all look identical, but the pistons are different... Dimensionally, they look the same, but the new ones don't have the little 'teeth' apparently keep the pistons from rotating in the cylinder. It may be a stupid question, but is it okay to run these pistons? I would just use the old pistons in the new housings, with the new rubber, but they are siezed in there good and one of 'em is really, really pitted.
It's perfectly safe to use them. There is no rotational force to cause the pistons to rotate in the cylinders, and if they did rotate it would cause no harm
The Jalopy Journal
