phenolic or metal caliper piston?

[ShafferNY]

I'm thinking about replacing both rear calipers on my Liberty, but retailers sell two different types; phenolic or metal piston calipers.

From the short amout of research I've done, the phenolic is supposed to transfer less heat to the brake fluid and caliper/axle, but also has the tendancy to stick in the bore. (OEM calipers are phenolic)

Metal piston calipers have much less tendancy to stick, but tranfer heat more as it is a better conducter.

Any opinions?

My first thoughts are, if they used metal for years without issue, whey go to a plastic composite?

 

[tjkj2002]

Get the medal piston caliphers and flush all the old fliud out and replace with DOT4 brake fluid which has a much higher boiling point then the OEM DOT3 brake fluid.

Just basically bleed the L/R calipher until you go through about 1/2qt of DOT4 fliud then bleed the rest of the caliphers until the fluid comes out nice and clear.Watch the fluid level,you do not want to run the master cylinder dry then you get to remove the master cylinder and bench bleed it(not fun).You will most likely see alot of black chunks come out of the brake lines when bleeding,that would be pieces of the composite piston that got scraped off in the calipher bore.Just remember you need to flush the brake fluid about every 2-3 years,it's the most neglected fluid but one of the most important,go figure.

 

[offrovering]

you may or may not need to soak your bleed screws with PB blaster, I had one that was giving me hell.

i bled my system yesterday after I installed a new driver side rear caliper. my old fluid was actually ok, a little dark, but not chunky, and surprisingly, I had no air in the lines anywhere after 95k

I got the metal grade piston.

 

[ShafferNY]

I bit the bullet and ordered two reman. calipers today. $210 and another $70 for cores. I got the metal piston ones though.

I didn't realize these calipers were used on the Ford Explorer of the same years.

 

[offrovering]

where did you get them? mine was from napa, I liked the reman better than what I took off. my banjo bolt on the back of the caliper was seized pretty good too, everything under/back there was nasty, took some soaking.

 

[ShafferNY]

I ordered them from Advance Auto. It was about the best deal I could get on metal piston calipers. They have a lifetime warranty on them, so I figure it's worth it.

I plan on changing the pads and fluid at the same time.

 

[tan's2002kjlimited]

My first thoughts are, if they used metal for years without issue, whey go to a plastic composite?

Weight reduction . A little here, a little there, in the end, it all adds up.
Anything to get the MPG's up.

 

[ShafferNY]

Weight reduction . A little here, a little there, in the end, it all adds up.
Anything to get the MPG's up.

It all adds up to an inferior product. If it ain't broke, don't fix it I say.