I did a search on brake issues and I see that there are some existing discussions, but I wanted to start a new post due to the issues I'm having with Ford service. Let's see what you all think.

I own a 2011 F-450 that I purchased new. Previously, I drove a 2008 F-350 that I had purchased new. I bought these trucks to pull my horses trailers. The '08 would not pull my trailer without chucking and after working with the Ford FSE, bought the '11 "based on the FSE recommendation".

In January this year, I drove home from a short trip to town (about 20 miles) and when I got out of the truck I smelled a STRONG burning smell from the left front wheel well. It didn't occur again, but when I took the truck in for servicing I asked them to check it out. Ford service said they "could not reproduce" the issue, nothing was done.

In February, once again driving a short distance to town, noticed smoke coming out of wheel well. Stopped and saw smoke pouring out of brake on left front. On a Sunday of course, so took the truck to Ford service Monday. They "could not reproduce", so nothing done.

In March, drove approximately 43 miles with a trailer at highway speed, picked up a horse and began to drive home. At about 25 miles I began to experience a shudder, which became so bad within about a mile that I had to pull over. Called Ford to notify the service writer and told him I'd have to wait for the brake to cool off since I was pulling a horse and trailer and couldn't have the truck towed to Ford. Of course it was Friday at 5:45 p.m., so I had to wait for Monday to take the truck in for service. Once again, "we cannot reproduce the problem", so nothing done.

Keep in mind that this is a truck that is still under warranty. But the dealer tells me that they cannot do anything unless they can reproduce the problem and determine what part they need to replace.

After my complaining LOUDER, the service manager has now put a request in for the FSE to come and look at the truck. It's been going on two weeks and I am still waiting. I am stuck without a truck and cannot haul my horses. I am stuck in Texas, when I should have headed north to Montana a month ago per my work schedule.

But REALLY, we are now going on the fourth month of trying to get resolution on a truck under warranty. Would you want your wife/mother/sister hauling for thousands of miles with a truck that would probably leave them stranded by the side of the highway alone?

 

The soft brake line has a partial blockage from poor assembly where when the ends were crimped on some of the hose got in the way and it creates a partial obstruction as things heat up. Just an educated guess. I've see it before. They should take it all apart and inspect the slider pins and the caliper itself. Could be a bad caliper as well? You should get new pads out of the deal and a rotor too if its burnt. Make sure they power bleed the hell out of it as well.

 

I'd be thrilled if they anything. To date they have refused to do any work. But thank you for your advise.

 

I agree with the brake flex line.

 

You definitely have a brake hang-up, and it would not matter if you were towing the trailer or not. The problem with the hunt is what is causing the issue?

Intermittent hang-up is the hardest for the dealer to sort out, but the dealership should be willing to invest in the time to go for a longer test drive and take one of the mechanics heat guns with him.

The last situation you talked about with the shuttering is due to temporary thermal distortion of the rotor. This is not like the typical pulsation caused by worn disc thickness variation that most complain about. This occurs when there is an extreme amount of heat buildup in the rotor, causing it to bend in a manner like a wave washer. And the only situation for that to occur is when the brake pads are continually in contact with the rotor.

I’ll explain the situation. If the brake pads cannot move away from the rotor the 0.010” or more that they need to for cooling and are in light contact, there will be friction and heat build up, although the light contact may not be enough to cause a pull. But as the temperature rises the pads start to expand and contact harder, progressing the friction and heat. If the cause is mechanical and not part of the hydraulics, opening the bleeder screw does not do anything while the problem exists. If the problem lies within the brake hose, then opening the bleeder screw will relieve the pressure and the brakes hold. If it comes back with the next brake application or not is very dependent on the tear in the hose. The condition may only occur with a specific pressure and while the hose is pulled or twisted in a certain way. You could possibly drive for hundreds of miles and not experience it again. Or in the next 10 miles.

If it is the hose, the situation becomes worse as the brake fluid is trapped while heating up, expanding and increasing the pressure more so then just a mechanical issue.

At the first customer concern the dealership should have opened the caliper assembly, checked for mechanical hang-up, and if it was me, replaced the brake hose just in case. A relatively low cost ($60-$70 MSRP) hardware preventative counterpoint as to be proactive to a customer who spent a lot of money on a F-450. (Not sure if you are still in warranty).

But at this point you’ve had a situation when a high degree of heat energy has gotten into these parts. Depending on the temp, there now can be distress in the pads, caliper and rotor, so they will need to be carefully inspected.

This type of situation drives me nuts when dealership service personnel takes a vehicle out for a short drive, does not have an issue and never looks at the brakes. The only thing I can think of is if this dealership is under the microscope by Ford for past warranty repair issues. There is no reason why a man or women should be parked on the side of the road in this type of transport situation, especially when they have been in for service.

When I first started out in the automotive brake industry I also sidelined working in the field of accident reconstruction with brake related accidents. I would suggest you keep all of your service paperwork related to this brake problem. A front left brake pull can have serious consequences, let alone being on the side of the road subjected to whomever comes by.

I don’t spend much time on FTE like I do on TDS, but I really hope the Ford Service rep sees this thread.

 

fmtrvt great explanation, very informative. Besides the brake issues I would think the heat being generated can't be good for seals and bearings either.

 

Thanks to each of you for your advise. I too am hopeful that the Ford Service rep sees this. Agreed there should have never been this much foot dragging. Makes for extremely poor customer service after spending ALOT of money for a larger truck based on the FSE recommending that I do so.

At this point still waiting on word of when the FSE will arrive to look at this truck.

 

Great write up Mr. fmtrvt. I did see one occasion where the caliper bore was milled out improperly(not deep enough) slightly limiting the piston travel in the caliper bore. I've also seen a flipped or rolled bore seal do this, made piston retraction slow. Those two were both a bear to trouble shoot root cause. We really had to dig.
I too have been in and around the industry(auto/heavy truck/industrial) and am always surprised at how warranties are miss handled at times. You could be spot-on about this dealer being micro examined. Treat this like a doctor diagnosing cancer...get a second opinion.
This is a brake issue not a door ****. That should immediately elevate the urgency to a safety issue! Look up Crystal here. She is our spokes person for issues like this and she will drive the flag up the right pole once you provide her with the pertinent info she will request. Please follow up and close out the thread with the resolution.

 

There are a few things that can hang up a wheel brake and it doesn’t matter if it’s an F-150 to F-550. While these foundation brakes are made by different companies, all disc bakes share common traits.

One necessity is for the brake to be able to cool down, and that’s part of the issue here. While repetitive stops certainly generate a lot of heat energy, when a brake does not cool between applications there are then cascading steps in the temperature rise. Everyone thinks that brake applications downgrade in the mountains is the worst, but so are city cycles. It depends on the amount of cooling time and airflow through the rotor. While industry tests in locations such as Townes Pass or Jennerstown, PA do generate high temps, vehicle tests in the center of LA, San Antonio, or Philadelphia where there are short city blocks can achieve as high or higher then those high percent slopes. You may only be going 25 mph between stoplights, but the slow rotation of the disc (low airflow) and the short time between stops elevates the temperatures.

In the case of this F-450, with the pads dragging on the rotor there’s no cooling time for that brake. So maybe after one application the rotor temps are up to 200°F evenly, at the next stop the IBT (initial brake temperature) is 200 / 150, rising 150°F at the FBT. Drive another mile and the stop IBT is 300 / 200. Usually it’s not that bad, but our test drivers would start to feel a brake pull when you would get to about a 100°F differential side to side with the pull going to the hotter brake. Most pickup brake pads are semi-metallic (and should be) and the friction vs. temp curve is bell shaped. There is a sweet spot usually in the 200 – 500°F range. The curve will move depending on the friction material compound. Higher metallic content, higher temp curve and more severe.

A brake that is smoking after a distance traveled can be caused by a number of things, but all that has to happen is a brake pad not releasing away from the rotor. All calipers are designed with a targeted seal rollback, depending on the composition of the square rubber O-Ring and the tangential grove in the caliper that it fits into. The groove is designed so that as the O-Ring slides towards the pad (along with the piston) it will compress tighter both in sealing and developing some distortion towards the pad. As pressure is released the O-Ring will return to it released position causing the piston to rollback it’s designed distance, 0.020” or whatever is selected.

Heat aging over time hardens the O-Ring and that’s why it’s good to replace or rebuild calipers during pad change out. In fact Ford and all the vehicle and caliper manufacturers test for this by placing the caliper in an oven for a set period of time, then measuring the rollback at a set pressure in a bench fixture.

http://www.linkeng.com/Libraries/Fea...spec.sflb.ashx

Any manufacturing defect in the bore, O-Ring groove, or Caliper Dust Boot groove can upset this ability, too. So can any rust that is not removed from these grooves during a caliper rebuild.

If you looked at the linked pdf you read about knock-back. This used to be a major part of having the pads move away from the rotor buy using the machined in lateral runout of the rotor to “knock-back” the pads (and pistons) to some extent. The industry got away from that almost two decades ago. The major cause of in-service brake pulsation is disc thickness variation, not the “warp” label commonly used. And the thickness variation is caused when the highest point of rotor runout abrades against the pads when you are not braking. And that is why you see more design emphasis on using bracket clips that will push the pads away from the rotor. So again it’s good practice to replace the calipers when pads are replaced to insure the best rollback and clearance, and also why for the last two decades there has been such a drive to have mechanics index rotors for minimal runout. And the necessity to absolutely check slide pins for freedom of movement, not only for improved cooling but also in an effort to minimize the possibility of brake pulsation.

Now that I’ve gone off a tangent getting all wordy, let get back to this F-450.

Anything that allows one or both pads to contact the rotor is going to cause a higher temperature. If only one pad you can have a very high temperature, getting the one pad over 1200°F, which is the point where there is a good quantity of visible smoke. Just smelling the formaldehyde and ammonia using can be in the 750-900°F range. (We used to have to run a Ford test based off a work in Germany where we would need to see if the brake pad would catch on fire.)

Now if one pad (and rotor) is getting hot you only notice the odor and possibly smoke. You may have some pull to that one side due to the pads elevated temp, but the wheel won’t be locking and you won’t feel any shutter while driving without applying the brake. Usually a one-pad issue is caused by either a brake pad hanging up in the bracket or caliper slides not allowing the outer pad to retract away from the rotor. The pad hanging up in the bracket sometimes is caused by rust on in-frequently operated vehicles that builds up on the end of the pad’s steelback where it fits into the bracket. With new pads, especially aftermarket, excessive paint on the steelback can cause this, or the pads steelback was manufactured too wide.

Pad hang-up can be easily checked with the caliper off the bracket and just seeing how easily the pad move towards and away from the rotor. Many of us at our test facility would apply a light coating of anti-seize to these points after checking for freedom of movement on our own, but not test vehicles. We had to follow production line assembly procedures for our test work.

The internal causes of a caliper not retracting its pistons were discussed earlier. This is a very hard thing for a mechanic to sort out. There is usually some sort of pad drag when the vehicle is on a lift and the wheel turned. How much is acceptable is a learned trait and is different between vehicle platforms and caliper designs. Or unless you have a caliper bench test unit or inertia dynamometer. Not going to have them at a dealership or garage. So for in-service work it will be a caliper change out.

There is something not mentioned earlier that can cause the pistons to not retract, and that is swell and growth of a phenolic piston. Phenolic pistons today are used almost exclusively and there are very good reasons for that, trying to keep as much thermal energy away from the brake fluid which could result in brake fluid boil with it’s characteristic brake pedal almost to the floor.

Most friction materials use phenolic resin as the binder to hold everything together until it carbonizes at the rubbing surface. If the piston manufacturer has done his due diligence the pistons go through a robust post bake cycle after being pressed, just like brake pads. If the post bake is proper and the correct type of phenolic resin used there should not be any issues. But if either is shortchanged the phenolic composite will swell under temperature. Sometime it comes back to size once cooled, and sometimes not. Depends on the reason for the S/G.

Depending on how firm the caliper hang-up is, the amount of heat and friction will build much higher then with only one pad against the rotor. Much higher temperature, a higher amount of smoke and odor, and the one brake can start to self apply. The rotor can also get so hot as to thermally distort. If you happen to be educated in this situation and brought along a wrench to open the bleed screw on that caliper, the result of no squirt of brake fluid and no release of the problem brake will tell it’s a caliper issue and not a hose or other issue trapping fluid.

The hose issue comes up with decade old vehicles usually, but anything that pulls the hose taunt that can cause an internal tear of the inner membrane, either in the line or close at a metal to hose connection. Sometime a hose is just poorly made. Sometime if someone has removed a caliper and the caliper weight pulled on the hose it can tear. Twisting the hose when installing the caliper is another issue, and well as when the vehicle is transported someone accidentally grabs the hose. A big issue is when the owner puts in even a mind lift not checking what happens a full rebound under a full turn. Hose problems happen.

With an internal tear of the hose the inner liner can act as a one-way valve, wither preventing the release of hydraulic brake pressure at the caliper or pressure at the caliper (non-apply). If the brake is hanging up with high temps and applied, open the bleeder screw and allowing pressurized fluid to escape solves the issue. When until the next brake application when the specific position of the hose aggravates the issue. You do one hundred stops in a row without a problem, but make one stop with the wheel turns a specific way, the compression of the suspension a certain way, and enough brake fluid pressure to go under the inner liner and expand the bubble and you’ve got a locked brake again.

This type of lock can get real nasty, lots of temperature, brake rotor distortion, and the vehicle pulling out of lane without application. Or a light pull then hard pull with the brake applied. Or going the opposite direction because no pressure is getting to that one caliper. It depends on the position of the internal tear.

The easiest way to check if you are developing a problem or confirming it is to check rotor temps with an infrared gun, just shooting it through the vents in the wheel of the rotor-pad swept area. The temps will vary on the driving conditions, of course the front to back brake bias of the vehicle, and lets not forget brake cooling. Depending on the driving environment you can have rear brake temps higher then front brake temps since the rear brakes do not get the same quantity of cooling air the front brakes get, and four wheel disc brake vehicles are never the “only the front brakes do the work” situation of 30 years ago.

The important thing is what is the left to right temp, that the differential does not exceed 75-100°F.

When a person does this it’s usually better to use a consistent point, usually about ½: from the OD of the rotor. A flashlight and the target light of the infrared gun will help with that.

I’ve got two guns but I’ll use the lesser-priced Raytek.



Here are the rotor temps after I have been driving around my neighborhood, 25mph area for 1.5mi, stopping at turns and stop signs. Again, I’ve said this in the past the Ford F-350 and like vehicles are relatively evenly biased in braking. The sequence is LF, RF, RR, and LR as I move around the truck.



Around a 20-25°F spread, not bad out of the driveway.

Pulling out onto the local road with 4 50-0mph stops every 1/2mi, no load in the truck.



Not very hot at all, but well balanced. There is not a lot of heat soak into the rotors, hubs and wheels, so if the truck had been operating for some time the temperatures would be higher. Some of the heat energy is dissipating into the other wheel parts mentioned.

Then a 2.5mi drive at 50mph, coasting to a stop.



All show a relative cool-down with no brake hang-up. Again, the rear brakes do not see the same cooling air flow that the front does. As you get into this type of brake temperature differential, the semi-metallic frictional curve can play a part. Depending on the temp differential, and despite have a smaller piston area on the rear calipers, you can be at a point where the brake bias is 50/50 or even shift rearward. Some disc/disc vehicles like the Freestyle used to wear out the rear pads faster then the front pads due to this situation.

So if you have access to infrared gun with the F-450, I would start to check brake rotor temps. Learn how to get consistent reading off the rotors, which can take some time to learn. With this type of brake issue taking readings after a few miles drive may be more telling then in town driving since the drag is effecting the cool-down. And it may take some time if the issue is intermediate; i.e. pressure, time, suspension and steering input. But keeping a notebook and taking cell phone or camera images of these readings may be the basis you need to get this particular dealership off their tail.

This may have started with only a brake hose issue. But now that you have had the situation with possibly very high temperatures, all of the brake on this wheel needs to be inspected.

I probably forgot some things, I was rambling and I didn't proof what I wrote, so I’ll be back another time.

 

I got your PM and responded, barrel racer. Let me know if I can be of any additional assistance.

Crystal

 

Update: I spoke to the Regional Service Manager who reiterated that the first step for a Ford dealer on any warranty work is that they must reproduce the problem. Also, that when the FSE comes to the dealer for other vehicles, the dealership will extend me the courtesy of having the FSE look at my truck. At this point, there is no eta on the FSE's schedule. So, in my opinion, as of today I am in the same situation that I have been since January. Ford will continue to do nothing about my brakes and I'll continue to drive my truck and wait until the next time that my brakes smoke or I am broken down at the side of the road.

I am so frustrated I don't know whether to scream or cry. I'm not an ignorant person; somehow I managed to earn a degree in engineering and build a successful consulting business. But after spending well over $100,000 on two F-series trucks that Ford told me as a customer would perform the work that I specifically bought them for, I am afraid to drive down the road.

P.S. FMTRVT, I have purchased an infrared gun to use in documenting this issue.

 

Well, took my first temperature reading after a drive. Right brake was 405 degrees, left brake was 915 degrees. Differential of 126%. I plan on driving different distances and will keep a record of temperatures.

FMTRVT, what is the max difference that you should see on the rotors?

 

Oops, I see in rereading the prior posts from FMTRVT that max differential should be 75-100 degrees F. BTW, still working on this issue. Just had the same issue with the right (passenger) front brake the other day as well with right brake at 920 degrees and left at 175 degrees. Now a matter of deciding on spending $1500 to replace both front brake systems or take a baby step or two first. I wish we could find out just how many brake caliper issues have been reported. I suggest every Ford owner that is having brake issues to report this to the NHTSA. It would only take a moment of your time and if they get enough complaints maybe Ford will need to do something about it "before" tragic accidents occur like with GM. Although that seems to be the only way to get attention with the auto industry these days.

 

More info to date: upon asking the Ford service dept to provide a quote for replacing rotors, pads, calipers and hoses, the service manager wanted to know if I wanted to go further and replace the master cylinder, the hydraulics and the proportioning valve. Well, according to my research, as of 2000 there is no proportioning valve. Also, the only way the master would be involved is if both brakes hung up at the SAME time. Which mine are not. I wonder what the requirements are for continuing education at Ford these days?

 

I would imagine it has to to more with profit than problem solving.