Brakes AGAIN !

groundhogy wrote:
So, I had a phone conversation with an engineer at Centric.

He focused on two things.

First was the rubber seal that seals the piston and piston bore (cylinder). He said with new calipers, the surface where the seal goes is almost mirror finish. On remanufuactured units, the surface gets sand blasted. So with the sandblasted surface that the rubber seal sits against, moisture/rust can creep in there easily. So in many returned cores, he sees alot of corrosion in that area causing sticking pistons.

His recommendation? When you receive the new remanufactured caliper, get a syringe and squirt a bunch of dielectric grease (superlube for example) under the seal and into that area. He also said you might even just take some silicone caulk and put that over the outside of the seal(although he hasnt tried this, but it just popped into his head at the moment). Doing this will help prevent moisture entry.

He also said that they offer a zinc plated and painted caliper. He says some of the plating goes into the bore a little bit. So if you order the plated version from Centric, this also will resist the rust effect.

The second observation.
He says that when you get uneven pad wear, one piston is out further than the other. But, both the back of the pad and the head of each piston is flat. So smashing these together makes the phenolic piston crook inside the bore. So when the piston crooks or cants or twists sideways inside the bore, it gets bite marks on it, material might get scraped off of the piston. Bad things.

I did confirm with him that they replace all pistons with new.

I still am in search of the Centric warranty on these units if anyone knows.

IMO - be careful with the information given by this person.

Another thought of mine...
So, say you have a 2003 F-250. Its getting older.
Say the brake caliper design is prone to sticking and gets replaced alot.

So now imagine you are the caliper. Say you were born in 2003. How many times have you cycled onto a truck and into a reman factory?

How manytimes has your little mirror finish surface been sand blasted?
How flat or how wavy is that surface now? lol.

And is there any other surfaces on the caliper that will degrade with many sand blastings?

So, I had a phone conversation with an engineer at Centric.

He focused on two things.

First was the rubber seal that seals the piston and piston bore (cylinder). He said with new calipers, the surface where the seal goes is almost mirror finish. On remanufuactured units, the surface gets sand blasted. So with the sandblasted surface that the rubber seal sits against, moisture/rust can creep in there easily. So in many returned cores, he sees alot of corrosion in that area causing sticking pistons.

His recommendation? When you receive the new remanufactured caliper, get a syringe and squirt a bunch of dielectric grease (superlube for example) under the seal and into that area. He also said you might even just take some silicone caulk and put that over the outside of the seal(although he hasnt tried this, but it just popped into his head at the moment). Doing this will help prevent moisture entry.

He also said that they offer a zinc plated and painted caliper. He says some of the plating goes into the bore a little bit. So if you order the plated version from Centric, this also will resist the rust effect.

The second observation.
He says that when you get uneven pad wear, one piston is out further than the other. But, both the back of the pad and the head of each piston is flat. So smashing these together makes the phenolic piston crook inside the bore. So when the piston crooks or cants or twists sideways inside the bore, it gets bite marks on it, material might get scraped off of the piston. Bad things.

I did confirm with him that they replace all pistons with new.

I still am in search of the Centric warranty on these units if anyone knows.

whjco wrote:
Have you checked the parking brake for a sticking cable?

I'm not the OP, but I've checked the parking brake on my truck and it's OK, but this has also happened with the front calipers. I've also had this problem since the truck was new and all of those calipers have seized and been replaced so I haven't seen where it is a remanufacturing problem. But it does make me wonder if there was a supplier who made a bad caliper since some have the problem and some people don't.

Have you checked the parking brake for a sticking cable?

Have you checked the parking brake for a sticking cable?

I had a 94 ford explorer and got 320k miles on it.
Best vehicle I ever owned. Dont remember ever changing calipers! Lol

I am wondering if its not a ford problem but a remanufacturer problem?

I never saw or realized the Super duty brake caliper issues. Granted, the trucks I/ the company had were all 5yrs old or newer, but Had a contractor working for us that was running a huge fleet of old 6.0s that were 10 years old, in the Arctic and didn't see those issues. No road salt up there though. We wanted the roads to freeze! Lol

72cougarxr7 wrote:
I concur that the phenolic caliper pistons seem to be the cause of the Superduty sticking brake issue. I replaced all 4 calipers on my 2008 f350 last year, 1 piston in the rear and 1 on the front would stick and drag the brakes.
I had the same issue on a ranger I drove in high school.

On the rear of my F350, I was able to order new (not reman/rebuilt) Raybestos calipers from rock auto. They honestly looked better than oem quality.
I also siphoned the old fluid out of the master cylinder, put in fresh fluid, and let each caliper gravity bleed until fresh fluid came out. I plan on flushing the fluid once a year to keep fresh fluid in the system. Brake fluid absorbs moisture, which naturally settles to the bottom of the system, which is the calipers.

I believe you're right. But no need to do brake fluid every year. Most people don't do it ever. Fwiw, I do a "slow" brake fluid exchange. Every year or 2 I suck the mater cyl dry on stuff and refill a couple times. Uses more brake fluid but it works!

Ok, I have been reading other forums the last couple of nights...

I am reading that some of the caliper remanufacturers will reuse the pistons if they look ok to save money.

I have also read that the majority of binding incidents occur with the pistons getting stuck more than the guide pins.

There is also a good engineering reason that they use phenolic. I just cant remember it. lol. Temperature insulation? Or corrosion of the wet brake fluid?

Also read one guy where I guess he ended up with two mismatched pieces and the guide pin holes on both parts were 0.030" off. So no slidy good.

Anyway, I have searched and found two companies that DO replace the pistons with new units.

Centric and NuGeon

I went to the Motorcraft site and they probably do, but I cant tell for sure by the verbiage.

I am searching local sources, but they are both available on Rock Ahuto.

Im planing Centric. Have an email out asking about their warranty.