Hope I don't get in trouble for this

Rodbuster

Well-known member
I'm starting a new thread on brakes to try and get a "specific point" made clear or answered. There are several threads out there on brakes but it seems that they all get tangled up in...adjusting or axles or manufacturers or too much grease etc.etc.

Please don't take this as a complaint because, it is not. I personally, have picked up many useful ideas and thoughts from these posts.
Something was mentioned on one of these threads that really got my attention because of a brake problem that I am having. It was not elaborated on, and that is the reason for this post.

My problem (and it seems others have the same problem) is this.
I have a 2011 Ford F350 dually 6.7 diesel with factory installed brake controller.
Just purchased a 2012 Key Largo.
When I'm going down the road at about 25 or 30 or 50 mph the brakes seem to work OK.
"BUT" when I try to do my tug test when hitching up the 5th wheek I have no holding power "AT ALL".

A test that I tried was... I was at a complete stop with my rig all hooked up, I put my truck in gear (drive) and did not touch the gas pedal or the truck brake pedal. I was on flat dry pavement so naturally the rig started rolling. I slid the lever to my brake controller all the way to the left. The rig kept on rolling. Once again, please understand, this is at "idle speed. I then adjusted the gain on the brake controller to 10 which is maximum, no difference at all. The rig kept on rolling.

The post on the other thread that got my attention said this.
"Magnetic trailer brakes rely on wheel motion to get the shoe to contact the drum".
I would like to know "for sure" if this is an accurate statement. I kinda think quite a few other people would be interested in the correct answer. It would take a load off of my mind to know for sure, that "all" of my brake system is working 100%.
I would not have any problems at all using my chocks for the "tug test".

Thank you
Rodbuster
 

cookie

Administrator
Staff member
Good question Rodbuster. I am not a brake expert but I do understand how they work. I think. I do not have an opinion on the efficiency of the drum brakes.
Your braking mechanism has two brake shoes, a magnet, brake drum and some linkage. When you apply the brakes in your truck the controller sends a proportional amount of voltage to the magnets. Attached to the magnets are an actuating arm. Once the magnets get the voltage they are then attracted to the side of the brake drum. While they are sticking to the side of the spinning drum they move the actuating arm which in turn leverages the brake shoes to the circumferential portion of the drum thus slowing down the rotation. Braking.
Hope this sheds some light on the subject.

Peace
Dave
 

TeJay

Well-known member
Rodbuster,
Good question and you are correct there is a lot of talk concerning brakes. I'm a retired automotive instructor. I've not worked on trailer brakes much but here's some info regarding your concern. Most trailer brakes do not self adjust like has been the case for most cars and trucks drum brakes since the 60's. By self-adjusting of drum brakes I mean this. Evey time you back up and apply your brakes (drums only) they will adjust if they need it and they won't if they don't. This keeps the shoes close and the same distance for all of your drum wheel brakes. Your TT is new and from what I've read on these forums your drum brakes may not be adjusted correctly from the factory. If the shoes are not somewhat close to the rotating drum you will not get correct or equal braking pressure. The shoes are adjusted by turning a star wheel from the back side of the brake assembly. You can adjust one wheel at a time by lifting it off the ground (don't forget to use safety stands). Then insert a flat object into the adjusting slot and alternate spinning the wheel and adjusting the star wheel out until the drum begins to drag. Then back it off an equal amount for each wheel until it just freely spins with no dragging sound. Once the shoes are close try your test again. I'll bet they are out of adjustment and can't move enough to do their job. Do a search online to get a picture of what it looks like inside the brake assembly. A picture is worth a thousand words. Just google, "brake shoe adjustment procedure." There may be some other issues but until you verify that the shoes are adjusted correctly don't search for anything else.
Hope this helps.
 

boatto5er

Founding VA Chap Ldr (Ret)
Also, when you engage the Brake Controller on the Ford Factory Controller all the way, it should lock the trailer brakes. This is how I test my slider hitch operation (which I've never had to use in a real situation by the way).
 

jcarnevale

Well-known member
I believe I have the same factory brake controller in my 2008 F250. I keep the gain set at eight(8)which is a little aggressive, but it works well. One of the tests I do after rolling a few feet is to operate the brake controller to its maximum and stop the rig as a check of the system, it always comes to a smooth stop. I don't know too much about trailer brakes but it sounds like you may need to adjust the pads closer to the drums as TeJay said with one of these brake tools.IMAG0252.jpg
 

chief190

Member
Thanks Irvin 56 for you post as that is the best I've seen electric brakes explained in a long time. As a Ford Master tech I know that the factory controller will lock up brakes when just rolling it only takes maybe 3-6 feet of rolling to fully apply the presure on the shoes. Just so you all know at leastmy 2011 trailer is equiped with the dexter axles are self adjusting as most new electricbrakes are now. I personnelly looked at the mess of a brake system I had on mine despite all the grease that caused them to not work they are self adjusting and no manual adjustment should be needed.
 

danemayer

Well-known member
According to the new brochures, the 2012 Landmarks come with the Dexter axle with self adjusting brakes. My 2011 Landmark has a label on the window that says Dexter Axle. Last Saturday at the rally luncheon, the Landmark Product Manager confirmed that late 2011 Landmarks also have Dexter Axles and all Landmarks with Dexter Axles have Dexter self-adjusting brakes. Dexter confirmed for me that I have self-adjusting brakes when I spoke with them earlier this week about the problem I'm having.

I'm not certain, but I think this type of self-adjusting brake adjusts when braking while moving forward and doesn't require backing up the way cars with drum brakes did.

I'm skeptical about the comment that implied that the brakes don't have stopping power when the wheels are stationary. Mechanically speaking it doesn't make sense to me, and until recently, mine used to hold just fine when testing the hitch.
 

Willym

Well-known member
The OP's brakes seem to be working OK at road speeds which suggests that the magnets and adjustment are fine. It almost seems that the brake controller is not putting out voltage at very low speeds. Early Ford IBC's had little or no output at low road speeds by design. I believe that this was done this way to prevent the brakes from grabbing. I'm not sure if Ford has changed the programming on the later versions of the controller. However one would expect that the manual lever would override this.

My brakes will engage in less than a quarter turn of the wheel. This can be demonstrated by pulling the emergency brake cable and trying to turn the wheel by hand.
 

floridarandy

Well-known member
The OP's brakes seem to be working OK at road speeds which suggests that the magnets and adjustment are fine. It almost seems that the brake controller is not putting out voltage at very low speeds. Early Ford IBC's had little or no output at low road speeds by design. I believe that this was done this way to prevent the brakes from grabbing. I'm not sure if Ford has changed the programming on the later versions of the controller. However one would expect that the manual lever would override this.

My brakes will engage in less than a quarter turn of the wheel. This can be demonstrated by pulling the emergency brake cable and trying to turn the wheel by hand.

I wouldn't leave home without a pull test. For this reason alone I'd have my brake system professionally checked (truck with rig attached) to ensure that a pull test is possible...even if the rig rolling down the road stops fine! There are too many posts...and some this week...of folks with that "sinking feeling" as their 5ver lands on their truck's bed rails! My 2 cents.
 

bdb2047

Well-known member
Rodbuster,
I,have same truck and no problems with brakes.Do you have your controler set for electric brakes?There are 2 settings for electric and electric over hyd.When I got my truck dealer did not know of it or understand it.
 

Ray LeTourneau

Senior Member - Past Moderator
I don't know beans about the Ford integrated brake controllers but I do know that the lever on my Prodigy will hold/lock the trailer wheels at standstill.

At the rally, there was a backing plate with the adjustable brakes on a table in the rear of the hall. I was playing with the mechanism and it seemed that the actuator that actually moved the adjustment screw had to move a long way before it would actually work. I'm still on the fence regarding these self adjusting brakes on trailers. Hopefully, we'll hear a report from folks that have them and can confirm they really work.
 

Bob&Patty

Founders of SoCal Chapter
I'm with Ray. I have the prodigy and I can slide the tires on the Horn in a pull test. Your problem my be in the intergrated system. Might possibly be the setting is wrong for drum brakes.
 
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