Brake caliper Metal or Phenolic piston ?

-
rustytoolss

rustytoolss

Well-Known Member
Joined
Sep 26, 2013
Messages
972
Reaction score
73
Location
Clinton, Ohio
Which type of caliper piston is better Metal or Phenolic ? Would it matter if they were mismatched ?
 
My personal experience is I wouldn't use the phenolic. I've seen a lot of them swell and stick. JMO
 
I did a disc brake conversion, bought a pair of calipers Centric's both have Phenolic pistons. The right seems to work fine. But the left is not.
 
Given a choice, I prefer the metal piston. Phenolic pistons tend to crack chip and drag inside the caliper.
 
Phenolics were a good idea that doesn't work. Too high a failure rate (stuck pistons).
 
I was working as a tech at a White's Auto Store back in 1980 something and did a brake job on an Aspen. Everything seemed to check out and it stopped fine. The guy takes it across town and brings it back with a smoking left front! My first experience with the phenolic piston!
 
When I was working as a mechanic 1977-1997 I also had some problems with phenolic pistons. But since then did not know if they had gotten better.
 
I rebuild a lot of jeep calipers for a rear brake conversion and most of the phenolic pistons are swollen so bad I just toss the caliper instead of drilling or chipping it out a puller is useless. Might help you out.
 
I wouldn't give a nickel for every phenolic piston ever made. Wish I had a nickel for every one I've replaced on F150 pickups.
 
Why ? At the moment I have 1 phenolic caliper that's working fine. But only need to replace the drivers side.
 
Why? Steel and phenolic plastic will expand and contract at different rates. I for one would not want to assume that they will work the same. Hey it may be working for you fine right now. I will not take that risk.
 
The whole Idea was to prevent heat transfer to the fluid. DOT 4 fluid can pretty much handle most high temp applications now so no need to worry there. If what you have works I wouldn't really worry about the mis-match. I think those calipers are pretty cheap though.
 
rustytoolss said:
Why ? At the moment I have 1 phenolic caliper that's working fine. But only need to replace the drivers side.
Click to expand...
My why,,,, Because I cant buy a just a pair of brake pads. Always a box of 4.
Phenolic pistons are going to stick, no ifs, just whens.
If it starts sticking far enough out, you will burn up a pair of pads, maybe damage a rotor too. If you wanna jack the car up now to do one side, and again later to do the other, have fun. If you want to always stop in straight line, do both sides the same and at the same time.
 
You must log in or register to reply here.
-

Back
Top