Thank you!

Steve

 

I have a 2000 F250 4x4 and a 2006 F350 4x4, the 2000 I have had for many years and have replaced all the calipers at least 2 times from sticking pistons not sticking slide pins. Pistons have never shattered on that truck. I just did the rears on the 2006 which I have had for only 2 years the pistons on the right side shattered from just removing the caliper from the rotor. First thing that came to my mind was what kind of crap are these things made out of if they shatter like this?

 

quite possibly my favorite forum response ever.

As for the caliper, I had one on a 12 F150 that was destroyed when a piston stuck, ripped the boot and pretty much destroyed everything caliper or rotor related at 55 mph. That truck led a hard life though pulling a 10k GN before we upgraded to a super duty. I wouldn’t call your issue common, though I wouldn’t say it’s unheard of. I agree that pulling something like that off the truck is unacceptable whether manufacturing or maintenance (not accusing you of poor maintenance) related. A caliper in that state definitely not ideal or safe for pulling the kind of loads these trucks are designed for.

 

You guys are wild over here. The 6.0 forum is much more accepting hah.

I was proud of my caliper explosion. That's why I took the picture. With how hot that bad boy was, and the smoke coming off of it- its amazing it didn't weld its self on

 

NEver seen that but... Did the caliper come off easy or did you have to use force ? Always push back the pistons first before taking the caliper off. If there is a ridge on the rotor edge you can put a ton of pressure on the pistons in the wrong direction. (sideways).
Just a guess though. It hasn't been a common thing here on ft's I think.

 

I had one on my '07, shattered a piston on the passenger rear caliper. Net result was every time you hit the brakes the fluid would squirt onto the hot rotor, producing a boatload of smoke. Not so good for stopping but great if someone is drafting you.

 

I'm not sure what some people drag me into these, or why I let myself ......

Long extension of the pistons, I'm guessing frozen. All of these had compromised botts from heat, can't say if the boots degraded then the calipers froze, or the boots degraded because of frozen pistons.



Moderate to long piston extension.




Long piston extension.





This was from an Excursion. Because they were being shipped to Germany, Ford required us to run the AMS thermal test which the Auto Moto Sport German magazine would run on vehicles in the Alps to see if the brake pads burned, and for how long.

New calipers, ran the two-day test, inspected, then parked the Excursion in the parking lot for a few months. It's not uncommon to have flames off the pads, and it's typical to have the boots burn. the early Excursions with the Akebono calipers had a stainless steel thermal barrier attached to the back of the pads. This was when we pulled it down to run other tests.

Stainless plate and the typical noise insulator retention nubs - the reason you have to push back on the pistons before moving the calipers off.








The caliper boots would look OK unless you viewed them carefully. In time, brake fluid would show. Brake fluid being extremely hygroscopic, it doesn't take long for the water absorbtion from high humidity days to go under the boot lip and freeze the pistons in place. Normal stops with a vehicle develop about 250psi hydraulic pressure, and on the backs of these pistons becomes 900 to 1,100 lbs of force, easy to overcome frozen pistons, but they don't retract with rusted piston bores. It starts to cascade.






Pictures of the Excursion test caliper and pin boots after sitting in the parking lot. The heat thrown from the rotors usually does a number on the sliding pin boots.

 

You drag yourself into because you love setting everyone straight with proper info.

Mine was seized. Drove it for a while to get it home, It was so hot I thought it was going to light up. I thought I was going to have to cut the caliper off. It was something special thats for sure,

 

Also... akebono caliper?

 

In 1997 Akebono won the brake caliper contract for the 1999 Superduty P131 contract from Ford. They did an outstanding job, took it right out from under TRW, because TRW was too confident it was theirs. So from initial launch in 1999 to ‘04 on the pickups, and all years of the Excursion, Akebono supplied the calipers they designed. TRW designed and supplied the rotors.

With the upsize of the tires and GVW for 2005, a new set of larger calipers and rotors were necessary. TRW got the contract for the calipers and rotors, the pricing reflected the desire to get the business back, not necessarily any technical advantage.

Akebono has been a caliper supplier to the Japanese automakers for a long time and still are.

 

Just curious. I bleed the brakes about every 50,000 miles to help keep fresh fluid in the calipers, or to give myself piece of mind. How often do you? Another observation, when I tow, light or heavy, although I rarely go over 70, I am also conservative about braking. Too many times I see people towing Heavy going like a bat out of hell then working their brakes hard. No wonder things are breaking, no pun intended.

 

I go by time, 3 years, not mileage. The reason we now have phenolic pistons just about universally is that consumers were not changing the brake fluid, and then manufacturers stopped putting it in the service intervals. Europeans tend to do it more. DOT 4 starts with a higher boiling point, but in three years drops to the same as DOT 3.

Doubling the weight being moved (trailer) doubles the energy dissipated during braking, so heavier trailers can really load the truck with poorly synchronized brakes.

Speed, however, squares the energy. 30mph to 60mph is a whole lot more. So is stopping distance.






Now everyone says I've got my brakes adjusted, but if they are drum brakes they do not have the same consistency per deceleration rate then discs. Its why today's disc/disc trucks can stop at between 60/40 to 65/35 axle bias while disc/drum was at 70/30 to 75/25. Trailers never match the tow vehicle, and why in the last years NHTSA has pushed for more ability when towing.

 

I have broken rotors on my 08 and my 2013. Things happen. Proper inspections, cleaning prolongs the life.

 

Thanks for taking the time to dissect the issues and explain them in a non-condescending way.

I hope people (like myself) learned something from this thread.

 

I always combine the brake bleeding with cleaning and greasing the slide pins. I do it at about 30k. I live in a very dry climate so moisture is less of an issue and the calipers barely rust.