TT Brake Service

Gdetrailer wrote:

alexey75 wrote:
Actually I experienced a sway last year. It was pretty windy day with gusts up to 50-60mph. We were driving for about an hour. We were going at a speed of 55-60 mph.
At some point it felt like truck applied full brakes on the trailer for split of a second.
It was very sudden/scary, I didn’t notice any sway before that. The good thing that the message came up on instrumental panel, saying some like: sway control... reduce speed...
Maybe it recognized the sway even before I noticed it :?

Correct.

Your vehicle has a sensor array located on the transmission hump between the drives and passenger seat, detects the movements of your vehicle and compares that to your steering wheel position and driver input to help determine if everything is all good or not.

Nice to have these systems BUT..

I would recommend checking your load weight distribution on the trailer. It is possible your tongue weight may be on the light side. Instability can also be caused by adding too much weight behind the trailer axles. May tow perfect under idea conditions but add some cross winds and it may no longer..

Generally TW should be 10%-15% of the trailer weight, however, the lighter the TW compared to the trailer weight the less stable it becomes.

I personally target 15% which is where the trailer will be as stable as possible.

Granted, there will be times under the wrong combination of conditions that can upset the whole train and cause some instability and you will have to ride out the process of regaining control.

I'm agree with you, nice to have it, BUT... I like to be able to control myself as well.

Lynnmor wrote:


I will never use the EZ-Lube grease zerk because of the excessive amount of grease in the hub and the very likely chance of grease getting on the brakes. Thoroughly clean the bearings and inspect them, then grease by hand. I use the grease gun to flush the old grease out of the hole in the spindle while it is apart, then never use it again. Do it right by hand and don't depend on gimmicks like EZ-Lube.

Completely agree and after seeing a new fifth wheel brake loaded with grease from the Dexter factory, very few people are able to use the system correctly. Dexter has a good video on how it should be done, but I prefer doing it by pulling and inspecting the bearings and replacing the seals.

alexey75 wrote:
Actually I experienced a sway last year. It was pretty windy day with gusts up to 50-60mph. We were driving for about an hour. We were going at a speed of 55-60 mph.
At some point it felt like truck applied full brakes on the trailer for split of a second.
It was very sudden/scary, I didn’t notice any sway before that. The good thing that the message came up on instrumental panel, saying some like: sway control... reduce speed...
Maybe it recognized the sway even before I noticed it :?

Correct.

Your vehicle has a sensor array located on the transmission hump between the drives and passenger seat, detects the movements of your vehicle and compares that to your steering wheel position and driver input to help determine if everything is all good or not.

Nice to have these systems BUT..

I would recommend checking your load weight distribution on the trailer. It is possible your tongue weight may be on the light side. Instability can also be caused by adding too much weight behind the trailer axles. May tow perfect under idea conditions but add some cross winds and it may no longer..

Generally TW should be 10%-15% of the trailer weight, however, the lighter the TW compared to the trailer weight the less stable it becomes.

I personally target 15% which is where the trailer will be as stable as possible.

Granted, there will be times under the wrong combination of conditions that can upset the whole train and cause some instability and you will have to ride out the process of regaining control.

Actually I experienced a sway last year. It was pretty windy day with gusts up to 50-60mph. We were driving for about an hour. We were going at a speed of 55-60 mph.
At some point it felt like truck applied full brakes on the trailer for split of a second.
It was very sudden/scary, I didn’t notice any sway before that. The good thing that the message came up on instrumental panel, saying some like: sway control... reduce speed...
Maybe it recognized the sway even before I noticed it :?

JBarca wrote:
GD's findings on trailer anti-sway control and other systems has some merit to it. And makes one stop and think about it.

The truck is so integrated now with all these subsystems, it may not expect the driver to press the manual control button on the brake controller. And if the driver did do that, the manual action will change the yaw reactions of the system which it will do. But the input sensors to all the subsystems will also react and they try to reduce or induce something. Technically, they should have some kind of software to sense manual button being depressed and what to do with that.

This may be like the change from older non anti lock brakes to antilock brakes. Years ago, you were taught when driving in snow/slippery conditions to pump the brakes to not skid and lock them up. But when anti lock brakes came out, that is not what you do, you hold for foot steady and let the anti lock feature do its thing. And the first time you drive one, that ratcheting feeling in the front end is all "new" and foreign to you. No one really tells you all this when you buy a new car on the dawn of a technology change.

Thinking through all this, one needs to understand what is in a new truck with all these subsystems. They also need to use better language in the owners manual when the proven older ways that even Ford preached, have changed on the use of the manual brake button. A statement saying to the effect, the auto features of the new intergraded systems can be interfered with if the the manual brake control button is applied while under way. See pages XYZ on trailer sway control etc. Or something to that effect.

I would agree that the manufacturers NEED to do a much better job explaining these enhanced systems and how they work/interact, instead, they seem to have removed a lot of important information on vehicle features and operation and added nearly 600 pages of junk to explain in detail on how to use the "entertainment system"! :S

Ford in the past HAS done a better job with their manuals in the past but I have noticed a severe decline in details starting with my 2013 which dedicated 3/4 of the manual to how to turn on the radio.. The 2019 and 2020 manuals are no improvements there either.

It basically is left up to the consumer to accidentally find out things on their own..

GD's findings on trailer anti-sway control and other systems has some merit to it. And makes one stop and think about it.

The truck is so integrated now with all these subsystems, it may not expect the driver to press the manual control button on the brake controller. And if the driver did do that, the manual action will change the yaw reactions of the system which it will do. But the input sensors to all the subsystems will also react and they try to reduce or induce something. Technically, they should have some kind of software to sense manual button being depressed and what to do with that.

This may be like the change from older non anti lock brakes to antilock brakes. Years ago, you were taught when driving in snow/slippery conditions to pump the brakes to not skid and lock them up. But when anti lock brakes came out, that is not what you do, you hold for foot steady and let the anti lock feature do its thing. And the first time you drive one, that ratcheting feeling in the front end is all "new" and foreign to you. No one really tells you all this when you buy a new car on the dawn of a technology change.

Thinking through all this, one needs to understand what is in a new truck with all these subsystems. They also need to use better language in the owners manual when the proven older ways that even Ford preached, have changed on the use of the manual brake button. A statement saying to the effect, the auto features of the new intergraded systems can be interfered with if the the manual brake control button is applied while under way. See pages XYZ on trailer sway control etc. Or something to that effect.

Lynnmor wrote:
This is the exact quote from the manual written by a lawyer:

Only use the manual control lever for proper adjustment of the gain during trailer setup. Misuse, such as application during trailer sway, could cause instability of trailer or tow vehicle.

Umm, if you are swaying, aren't you already experiencing instability?

The next sentence says you are not to tow during adverse weather, so maybe it is best to just stay home.

While the manual does not specifically state, I suspect it has a lot to do with how interconnected the Stability control, Roll control system, Trailer sway control, Side wind stabilization control, brake system and IBC system and even the power train (engine and transmission) are highly integrated together.

Manual activation of the trailer brake has the potential to interrupt or alter the operation of the other systems which may or may not be a good idea or ideal.

From the manual..
"Page 227

STABILITY CONTROL PRINCIPLE OF OPERATION

The system automatically turns on each
time you switch the ignition on.
If the stability control or traction control
system detects a fault, the following may
occur:

The stability and traction control light
illuminates steadily.

The stability control and traction
control systems do not enhance your
vehicle's ability to maintain traction of
the wheels.
If the stability control or traction control
system activates, the following may occur:

The stability and traction control light
flashes.

Your vehicle slows down.

Reduced engine power.

A vibration in the brake pedal.

The brake pedal is stiffer than usual.

If the driving condition is severe and
your foot is not on the brake pedal, the
pedal may move as the system applies
higher brake force.
The stability control system has several
features built into it to help you maintain
control of your vehicle.
Electronic Stability Control
The system helps to prevent your vehicle
skidding or laterally sliding by individually
applying the brakes to one or more wheels
and, if necessary, reducing engine power.
Roll Stability Control
The system helps to prevent rollovers by
detecting your vehicle's roll motion, and
individually applying the brakes to one or
more wheels.

Page 228

Side-Wind Stabilization
The system applies the brakes on one side
of your vehicle to reduce the effect of a
sudden side-wind gust on your vehicle's
path. When the system turns on, the
stability and traction control light flashes,
and a message may appear in the
information display. You may notice a
slight deceleration and may still need to
make a steering correction to maintain the
intended vehicle path. The system does
not turn on for a continuous side-wind or
during turns.

Page 291

TRAILER SWAY CONTROL
WARNING:
Turning off trailer sway
control increases the risk of loss of vehicle
control, serious injury or death. Ford does
not recommend disabling this feature
except in situations where speed reduction
may be detrimental (such as hill climbing),
the driver has significant trailer towing
experience, and can control trailer sway
and maintain safe operation.
Note:
This feature does not prevent trailer
sway, but reduces it once it begins.
Note:
This feature cannot stop all trailers
from swaying.
Note:
In some cases, if vehicle speed is too
high, the system may activate multiple
times, gradually reducing vehicle speed.
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.

Page 308

The controller interacts with the brake
control system and powertrain control
system of your vehicle to provide the
best performance on different road
conditions.

"


As far as towing in "adverse weather" goes, none of the truck safety systems provides "antilock" control for the TRAILER BRAKES Per Page 308..


Page 308


"Avoid towing in adverse weather
conditions. The trailer brake controller
does not provide anti-lock control of
the trailer wheels. Trailer wheels can
lock up on slippery surfaces, resulting
in reduced stability of trailer and tow
vehicle."

While the truck may maintain wheel traction via antilock brakes system, the trailer is all on it's own and if those wheels loose grip, well the results won't be pretty..

This is the exact quote from the manual written by a lawyer:

Only use the manual control lever for proper adjustment of the gain during trailer setup. Misuse, such as application during trailer sway, could cause instability of trailer or tow vehicle.

Umm, if you are swaying, aren't you already experiencing instability?

The next sentence says you are not to tow during adverse weather, so maybe it is best to just stay home.

alexey75 wrote:

JBarca wrote:

alexey75 wrote:

JBarca wrote:



OK, I know the self adjusting trailer brakes.

1. Do you "only" feel the "jerking", whenever it happens, occur when you are applying the brakes and then "stops jerking" when you stop applying the brakes?

2. OR, does the jerking start when you have applied the brakes, and may continue for a short while even after you stop applying the brakes?

3. The key point it, the issue "starts" with a braking action, yes or no?

Please answer all 3.

John

John,

We bought this trailer about a year ago, and during the summer I've experienced it probably 5-6 times.

1. It happened when I have applied the brakes during the slow down, like before the traffic light. When the speed was around 10 mph I've felt the jerking for a second, just before it came to full stop.

2. No, it didn't happen when I applied the brakes. And it didn't continue when I stopped applying the brakes.

3. No, it doesn't start with the braking action.

I've mentioned before, I've read in truck's manual that the truck stop applying the TT brakes when the speed below 12 mph (or something like that).
Any chance it's related to truck and not trailer?

What year, make and model truck do you have? I looked and cannot find it in the thread or your profile.

Does the truck have an integrated brake controller or an aftermarket one? If aftermarket what make and model.

Not sure I ever heard of a brake controller that stops working on the way down in speed. But it maybe, not sure why though.

And yes, some integrated brake controllers do drop off current while the truck is standing still and you have your foot on the brake, but by then you are stopped and not moving.

Thanks

John

PS, this one is a bit of a mystery as it seems to point to only low speed, please confirm, it is only low speed coming to a stop. I'll hold off on speculation until we know more about the truck and brake controller. I have had trailer brakes do strange things that sort of lock up creating some of what you are describing , but not with this only low speed issue.

It is 2018 f150 with integrated brake controller.

Found it :)
The trailer brake controller is equipped with a feature that reduces output at vehicle speeds below 11.2 mph (18 km/h) so trailer and vehicle braking is not jerky or harsh. This feature is only available when applying the brakes using your vehicle's brake pedal, not the controller

https://cdn.dealereprocess.org/cdn/servicemanuals/ford/2018-f150.pdf
Page 308

OK, there is a difference between "stops applying" below a certain speed and "reduced output" below a certain speed.

I have the first generation 2005 Ford intergraded brake controller, the one that will not allow the manual lever to work until the truck has gone over I "think" like 15 mph. It will let me manually brake to zero speed, just not on the way up. There was so many complaints on this that after Feb 2005 builds dates, they will apply brakes manually at zero speed.

And mine does reduce output once I am stopped.

Your 2018 has more setting then my vintage and it may be part of the issue you are having if it doing it's thing below 11.2 mph. Search around and see if other Ford 2018 or newer has this issues. There may even be a TBS about it.

Curious how this comes out.

John

PS. Reading page 308, 2 bullets up from the reduced output state, See here: https://cdn.dealereprocess.org/cdn/servicemanuals/ford/2018-f150.pdf

Ford is now saying you are not supposed to press the manual brake controller button if the trailer starts to sway. They are stating that is "misuse". Ford now states to only use the manual button for setting the gain. I'm not sure I agree with that. Pressing the manual button while driving straight ahead, and on purpose not using the truck brakes, used to be the first instinct go to action to help tame out a swaying trailer. I have not heard until I saw that tonight. WOW..!!! Do other brands of integrated controller now say this?

JBarca wrote:

alexey75 wrote:

JBarca wrote:



OK, I know the self adjusting trailer brakes.

1. Do you "only" feel the "jerking", whenever it happens, occur when you are applying the brakes and then "stops jerking" when you stop applying the brakes?

2. OR, does the jerking start when you have applied the brakes, and may continue for a short while even after you stop applying the brakes?

3. The key point it, the issue "starts" with a braking action, yes or no?

Please answer all 3.

John

John,

We bought this trailer about a year ago, and during the summer I've experienced it probably 5-6 times.

1. It happened when I have applied the brakes during the slow down, like before the traffic light. When the speed was around 10 mph I've felt the jerking for a second, just before it came to full stop.

2. No, it didn't happen when I applied the brakes. And it didn't continue when I stopped applying the brakes.

3. No, it doesn't start with the braking action.

I've mentioned before, I've read in truck's manual that the truck stop applying the TT brakes when the speed below 12 mph (or something like that).
Any chance it's related to truck and not trailer?

What year, make and model truck do you have? I looked and cannot find it in the thread or your profile.

Does the truck have an integrated brake controller or an aftermarket one? If aftermarket what make and model.

Not sure I ever heard of a brake controller that stops working on the way down in speed. But it maybe, not sure why though.

And yes, some integrated brake controllers do drop off current while the truck is standing still and you have your foot on the brake, but by then you are stopped and not moving.

Thanks

John

PS, this one is a bit of a mystery as it seems to point to only low speed, please confirm, it is only low speed coming to a stop. I'll hold off on speculation until we know more about the truck and brake controller. I have had trailer brakes do strange things that sort of lock up creating some of what you are describing , but not with this only low speed issue.

It is 2018 f150 with integrated brake controller.

Found it :)
The trailer brake controller is equipped with a feature that reduces output at vehicle speeds below 11.2 mph (18 km/h) so trailer and vehicle braking is not jerky or harsh. This feature is only available when applying the brakes using your vehicle's brake pedal, not the controller

https://cdn.dealereprocess.org/cdn/servicemanuals/ford/2018-f150.pdf
Page 308