Need help with the following issue on my 2016 F250 6.2 CCSB. Intermittently when I tow a trailer I will have a front caliper stick when braking. I’m calling it a sticking caliper but it could be something in the proportion of braking power from the truck to the caliper. I’m not entirely sure what the issue is at this point. It doesn’t do it every time, it will start and stop within the same trip. I have taken trips for many miles when it never showed. It is completely random in appearance. When it happens It really pulls hard when I apply the brakes. It has done this in both directions, left and right. At times it is so bad that I have to purposely steer in the opposite direction in order to stay in the correct lane. It has done this with a TT that has electric brakes and a boat trailer that has surge brakes. It has been to Ford and of course they cannot find an issue and keep blaming the trailer. I explained to them that it happens on different trailers with different types of braking systems, they don’t listen because they can’t test anything unless it is actually happening at that moment. I know this question will be asked, No it never braked like this without a trailer. I am at a total lose, we are scheduled to take a 4,000 mile trip shortly and I don’t want this issue to be a problem. Anybody have something like this happen? Any ideas where to look?

 

Do you have trailer sway control turned on?

 

I just use what the F250 has built in for towing. I have not tried turning anything off. Not sure what I should try.

 

Isn't it on by default every time you start the truck? I am just shooting in the dark here trying to figure out anything that can affect the brakes on your truck and that is all I would come up with. if you have that option under your settings try turning it off.

 

I watched a couple of youtube videos related to the sway control and can see how the truck might be applying the brakes to correct what it thinks is sway. It is worth a shot, next trip out I'll turn off sway control and see what happens. It must be something in the trucks electronics forcing the disproportional braking.

 

I wouldn't completely discount both trailers having the same issue.

would be prudent to adjust the brakes on both trailers so you know they aren't the cause of the pull. In even trailer brakes can cause a substantial pull when braking, but it is usually pretty consistent and gets worse as the trailer brakes get good and warm. To have it go both directions with the same trailer is truly odd.

are you sure it doesn't pull one way with one trailer and another with the other trailer?

it's possible too that a piston could be sticking when it is good and hot. But again, to have it go both ways would be odd.

if it were the roll stability or sway control, you should hear the ABS pump working while it is active. Do you hear the pump rub while it is pulling? Do you feel the pump push back against the pedal when it is acting up?

serving ideas.... things to think about.

 

caliper or slide pin issue is what it sounds like to me.

 

Its not the trailers because it is the same symptom and the surge brakes on the boat trailer are very weak, no way it could pull the truck to one side. I initially thought calipers or pins as well except it pulls left one time and right the next, I can't imagine both calipers having the issue and why wouldn't it show this with no trailer? This is a strange one for sure, if I can't fix it I might end up getting rid of the truck as it can be dangerous when it is really bad. I like the truck.

 

Doesn't the truck-based sway control only work if you put the sticker on the trailer tongue and then enable sway control in the menu? I'm fairly sure that my F-350 doesn't do anything about sway. Then again, my Andersen WDH controls sway well enough that I don't think there is anything for the truck to have to react to. I do not have the sticker on the tongue.

 

 

Thinking back about a year ago, I think I turned the truck based sway control feature off. As I recall, guys were reporting that the system was too active and was hurting gas mileage.

 

Again, the truck's trailer sway control does not continuously do anything to reduce sway. It only activates if the truck assesses it is about to lose control. It does NOT reduce fuel mileage, drag brakes all the time, and cannot be "too active". It gives a dash warning if it activates, too. If you have never seen a dash warning that says "TRAILER SWAY, REDUCE SPEED", you have never had sway control activate. It is an emergency safety feature that is reckless to deactivate for 99% of towers. Direct cut and paste from the manual:

This feature applies your vehicle brakes at
individual wheels and, if necessary, reduces
engine power. If the trailer begins to sway,
the stability control light flashes and the
message TRAILER SWAY REDUCE
SPEED appears in the information display.
The first thing to do is slow your vehicle
down, then pull safely to the side of the
road and check for proper tongue load and
trailer load distribution.

 

If I were dealing with an intermittent brake problem, I would get myself one of those inexpensive infrared thermometers. (Amazon has some models for $20 or so.) I would use it every day, on each wheel, to learn just what "normal" temperatures were, then, whenever the next time the problem occurred, I would pull off the road immediately and use it to look for a hotter than normal wheel. Since this is occurring with a trailer hooked up, I would also establish what "normal" temps were on it, and also check THOSE when I pulled over after the problem recurred.

I think that would give me a better idea of exactly where the problem is occurring.

 

there is nothing mechanical in the brake system that can sometimes make it pull one direction, and sometimes the other. If it is going back and forth, something else is causing it to do so.
likewise there is nothing in the ABS or roll stability that can cause it to do anything without being noticed. anything the RSC or Sway control does is both audible and tactile - you will notice it.

There's something missing. Something that makes the problem consistent and repeatable. Might not be something you have picked up on yet, but it has to be there otherwise there is no way to make sense of this.

I'll offer my personal anecdote as an example of what i mean.
my expedition would sometimes pull to the left when you hit the brakes, and sometimes it wouldn't. it appeared to be doing it at random and was driving me mad. Until i finally realized that it was darting left the first time i hit the brakes, and if i let off and hit them again it would stop straight. once i realized that it was completely repeatable and predictable and gave me a clue on what to fix. in my case, it was a slightly restricted brake hose. it would slightly restrict fluid going both directions, so it was slow to apply causing the vehicle to pull. but since it was also restricting it on the release, it didn't cause it to pull the next time you hit the pedal because the back pressure on that side matched the apply rate on the other. unexpected problem to have, but two new brake hoses on the front and it cured it.

there is some piece to the puzzle that keeps this from being random as you are describing it. just need that piece so that this all makes sense.

 

Do you have any trailer light issues on those 2 trailers? Lights not working, one side or the other dim, flickering, etc? I'm wondering if a short on your trailer brake circuit could be causing the sway control to freak out? How repeatable is this problem? If you go for a short drive around the block on your street, will it be long enough for it to happen? Maybe try a lap around the block with the trailer lights disconnected?

Hmm, I see you said "can go for miles" between incidents.

I'd be looking for gremlins in the trailer wiring. Know anyone with another trailer you can hitch up to and go for a drive?