phenolic caliper pistons

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bought venza used. found torn caliper piston boots from a recent brake job. recently learned about phenolic caliper pistons. never heard about those before today. front has dual phenolic pistons and the rear has steel caliper pistons. phenolic caliper pistons to me is similar to composite plastic valve covers and oil pans. company cheaped out and used cheaper material. my main concern is they are fine new, but will crack and wear over time. i'm reading that the pistons will swell over time and cause seizing. model year is 2013 with 70k miles. i'm looking for a steel piston but cannot find any available. visual top inspection is they look new and no cracks.

the only available options that i'm able to find are phenolic pistons CENTRIC 14546002 or CARLSON 7842. Ford explorers 2002-2005 seem to use this piston too. but i cannot find steel pistons anywhere.

should i just install the piston boots and call it a day or pull the pistons out for a cleaning and rebuild? the boot kit comes with the square cut o rings. i flushed the system since it was amber color and 5 years old.
 
You're welcome to think that, but the one car of mine that has phenolic pistons seems superior since the exposed piston won't rust and when you go to push it back during pad replacement it doesn't rip up the seal. As far as I know all the calipers are original to all my cars and I've never seen the phenolic piston crack, swell or in any way degrade.
 
Ford is famous for using Phenolic pistons and from what I've seen in the many brake jobs I've done, they are junk anything over 100k miles. They will shatter and fall to pieces when old, they will stick and cause calipers to seize when nothing else appears wrong. Ford chose to use these on the 03-08 Ford F250-F350 diesel trucks and they are promised to cause a failure at any given time when towing a load.
 
That's really something. I don't remember which one of my cars has those pistons, but which ever one it is can't be under 240,000 miles. Should I be worried?
 
Originally Posted by racin4ds
Ford is famous for using Phenolic pistons and from what I've seen in the many brake jobs I've done, they are junk anything over 100k miles. They will shatter and fall to pieces when old, they will stick and cause calipers to seize when nothing else appears wrong. Ford chose to use these on the 03-08 Ford F250-F350 diesel trucks and they are promised to cause a failure at any given time when towing a load.


Has Ford gone back to steel pistons for the newer Superduty trucks?
 
I have the option of phenolic or steel piston calipers for my 01 superduty. I am used to getting 2 or 3 years out of steel, so I tried phenolic. I figured since it's plastic, it would work great and wouldn't seize up in the bore.

I was very wrong. After 1 winter they seized up horribly. Apparently it swells really, really bad when exposed to corrosive materials. Such as salt spray or salt brine spray.
 
Well that's interesting, there must be different grades or quality. Here in the Great Lakes area we are swimming in brine spray during the winter.

Maybe I will go inspect them.
 
I can't say if Ford still uses them or not. I haven't done a brake job on a new SD truck yet.

If you have phenolic pistons, I'd highly suggest a thorough inspection on your next brake checkup. Most of the time they only crumble and fall apart when you remove the pads. Especially if they've been on a while. On the Fords, there is usually a metal "face" ring that goes over the piston and at first glance, you'll swear yours are metal...
 
These are the reasons that OEM's will specify phenolic caliper pistons:

1. They don't transfer the heat of the pads back to the brake fluid as well as steel pistons. This prevents fade.
2. The plastic doesn't rust, and for most of North America where people send their cars to the scrap heap with the original brake fluid, this might prevent seized calipers.
3. Less expensive than the steel piston, easier to produce, doesn't require plating.
4. Lighter weight, especially un-sprung weight is one of the Holy Grails for handling.

I don't like phenolic, but the cost accountants at the OEM's have to win sometimes.
 
Originally Posted by racin4ds
Ford is famous for using Phenolic pistons and from what I've seen in the many brake jobs I've done, they are junk anything over 100k miles. .


I got 23 years and 200,000+ miles out of the phenolic caliper pistons in my 1993 Ford Ranger
 
Originally Posted by racin4ds
Ford is famous for using Phenolic pistons and from what I've seen in the many brake jobs I've done, they are junk anything over 100k miles. They will shatter and fall to pieces when old, they will stick and cause calipers to seize when nothing else appears wrong. Ford chose to use these on the 03-08 Ford F250-F350 diesel trucks and they are promised to cause a failure at any given time when towing a load.


The gasoline versions do it too.
 
My 96 Grand Marquis has these and I am close to 200,000 miles on original calipers. Only second set of brake pads too. This car seems very easy on brakes and tires both compared to other cars.
 
Only one experience with phenolic, and it wasn't positive. Was working fine, pads fully worn out, so I pushed the pistons in and it immediate ate the pads in 3 month's time. This was on a 2014-ish Sonota with 190k, give or take--not that old.

But anything old is problematic?
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Not trying to read too much of my one datapoint but I'm starting to wonder if 200k isn't a bad time to just shotgun calipers and what the heck, hoses too. If not 200k then 10 years.
 
I certainly believe it has its place but I can assure you it does not belong in a 3/4-1 ton 8500lb diesel truck!!! I too have had great luck with them in passenger cars.
 
I am not a fan of the phenolic caliper pistons. I owned a 1985 Ford Ranger with the phenolic pistons, on 2 occasions, a front caliper piston stuck. Once I limped it to a girlfriends house and changed the caliper in the driveway, the other time it stuck so bad I had to limp it to a local shop and have it changed, rotor was glowing red!

My current 2008 F350 also has phenolic, had to change all 4 calipers out due to stuck or degrading phenolic pistons in the past year.
 
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