Brakes grabby at low speeds

RoyB wrote:
I know my Electric Brakes are 'grabby' when I first start using them on the trip. Here at the house I hook up and test safety lights and all then start leaving the housing area.

My trailer brakes are very 'grabby' doing the initial tests to see if they are working.

I have a full stop zone about 400-500 feet up the road after we start out still inside the housing area. I will use the manual slider for the trailer brakes to stop both and trailer at this stop sign...

All seems to clear up for me after doing this...

My Electric Brake controller is a built-in FORD OEM Brake Controller...

Goggle Image

I suspect this 'grabby' condition is due to accumulated moisture on the Brakes while sitting at the house a long time not being used.

A side note for my 4WD Jeep - This grabby situation reminds of the few times I replaced the clutch in the Jeep manual transmission. I always had this same 'grabby' condition and would pop a few heads until it wore-in and was smooth to use. I have on several occasions nosed up to a tree and slipped the clutch at high RPMs doing the so called burning-in of the clutch. Sure got a few strange looks from folks while I am trying to push this big tree over with my trusty ole Jeep haha... Smoked up the Jeep clutch pretty good doing this but the end result was always a smooth operating clutch after that. No telling how many miles of operations was removed from the clutch doing this haha...

Roy Ken

You are doing something wrong.

None of my trailers have issues with grabby brakes at low speed or high speed, cold or hot, in moisture or dry.

I set my Ford IBC to 4.5 which in my case WILL LIGHTLY STOP truck and trailer on level ground while engine is at idle when I operate the manual brake lever.

No need to set controller to the max if your brakes have been adjusted correctly AND you have GOOD WIRING.

When driving I feel NO DIFFERENCE in braking whether I am trailering or not.. In other words my trailer brakes are just SLIGHTLY "leading" the truck brakes..

Setting the brake controller too high can lead to the trailer brakes overly aggressively leading the vehicles brake giving the feeling of grabbiness..

Setting the trailer brakes too low can lead to the feeling of no brakes and will pose a potentially dangerous condition of over heating the vehicles brakes.

There IS a "fine line" at the point of just enough, not enough and over the top way too much trailer brakes.

Some folks have a difficult time getting over the feeling of trailering, it takes time to find that sweet spot.

OP needs to read the manual first then use the boost settings at the correct time.

HERE is the online manual.

Per manual..

"5
Adjusting the Power to the Trailer Brakes
(Prior to setting Boost)
Once the control has been securely mounted, it is necessary to set the power needed to stop the trailer during a braking event.
1. Connect trailer to tow vehicle.
2. With engine running set power (with Power Buttons) to indicate 6.0
3. Drive tow vehicle and trailer on a dry level paved surface at 25 mph and fully apply Manual Knob.

If trailer brakes lock up:
Turn power down using Power Buttons.

If braking was not sufficient:

Turn power up using Power Buttons.

4.
Repeat Step(3)until power has been set to a point just below wheel lock up or at a sufficient force as to achieve maximum braking power.

5.
Using the brake pedal, make a few low speed stops to check the
power setting. Trailer braking is initiated and terminated via the stoplight switch. When the brake pedal is released, trailer braking will cease.

Boost Setting
The boost button was designed to allow a more aggressive setting for your trailer brakes and is available in three levels - B1 , B2 , B3 .

Each incremental boost setting increases the sensitivity of the P3’s inertial sensors enhancing the participation of the trailer brakes during a braking event.

Truck/Trailer B1 icons on the screen indicate Boost On.

For example:
With the boost off, during a braking event, the power to the brakes starts out at zero and increases with deceleration.

With the boost on level 1,

B1, during a braking event, the power automatically starts out at approximately 13% of the power setting and increases with deceleration.

With the boost on level 2, B2,or with the boost on level 3,

B3, during a braking event, the power automatically starts out at approximately 25% of the power setting and increases with deceleration."

From ETRAILER they give you a clear chart on how and when to set the BOOST levels..

"Power Boost for Heavy-Duty Towing

Aside from smoother, more efficient braking, Tekonsha's P3 brake controller also offers a boost feature that gives you more initial braking power for those times when you're towing heavy loads. You can switch boost levels so that the power output to your trailer brakes automatically starts out at either 13 percent or 25 percent of the predetermined power setting.

So, if you boost the initial power so that your trailer brakes activate with 25 percent of the overall intensity at the start, the brakes will reach maximum braking faster. This is particularly beneficial if you are towing a heavy load because the intensity required to stop that load may be far greater than that needed to halt your vehicle. Therefore, sending out more initial power to the trailer brakes - and causing them to reach maximum braking faster - allows you to better control the trailer so that it doesn't push your tow vehicle before coming to a complete stop.

If your trailer weighs less than your tow vehicle, no boost is needed. But if you wish to set the boost so that your trailer leads the braking of your towing setup, you can select level B1. The following table gives an indication of when you might use the different boost levels and the power increases that they offer.

Approximate Gross Trailer Weight Boost Level Increase in Initial Power Output

Less than tow vehicle GVW B1 13%
Equal to tow vehicle GVW B1 or B2 13% or 25%
Up to 25% more than tow vehicle GVW B2 or B3* 25%
Up to 40% more than tow vehicle GVW B3* 25%

*Both B2 and B3 offer a 25-percent boost in initial power. But the braking curve for B3 is more aggressive than that of B2. This means that, even though you will start out with the same intensity when using these boost levels, you will get an overall more aggressive braking experience with the higher level. So if you use B3, you will reach maximum braking sooner than if you use B2"

I know my Electric Brakes are 'grabby' when I first start using them on the trip. Here at the house I hook up and test safety lights and all then start leaving the housing area.

My trailer brakes are very 'grabby' doing the initial tests to see if they are working.

I have a full stop zone about 400-500 feet up the road after we start out still inside the housing area. I will use the manual slider for the trailer brakes to stop both and trailer at this stop sign...

All seems to clear up for me after doing this...

My Electric Brake controller is a built-in FORD OEM Brake Controller...

Goggle Image

I suspect this 'grabby' condition is due to accumulated moisture on the Brakes while sitting at the house a long time not being used.

A side note for my 4WD Jeep - This grabby situation reminds of the few times I replaced the clutch in the Jeep manual transmission. I always had this same 'grabby' condition and would pop a few heads until it wore-in and was smooth to use. I have on several occasions nosed up to a tree and slipped the clutch at high RPMs doing the so called burning-in of the clutch. Sure got a few strange looks from folks while I am trying to push this big tree over with my trusty ole Jeep haha... Smoked up the Jeep clutch pretty good doing this but the end result was always a smooth operating clutch after that. No telling how many miles of operations was removed from the clutch doing this haha...

Roy Ken

deltabravo wrote:
New brakes is the problem. Trailer brakes don't work all that great until they have quite a few start / stop cycles on them. In other words, they need to be burned in.

I did RV transport for 2 years. I ALWAYS had to run my brake controller at max setting to get much braking action for the first part of the trip. By the time i reached my destination 224 miles later, the brakes were working better, but just barely, because the trip didn't involve much stopping and starting.

Absolutely wrong.

OP SAID it did this with a previous popup and a different tow vehicle but SAME CONTROLLER.

"New" brakes often are LESS effective until they "BED IN" to the drums.

The problem is the CONTROLLER and/or SETTINGS of the controller.

The controller is overshooting while driving slow and OK while driving at highway speeds.

OP NEEDS to reread the setup instructions for the controller and follow them to the "T".

If I remember correctly, you use the BOOST settings for higher speeds and remove the boost settings for slow speeds and backing up..

A P3 is not a "set and forget" controller, it does require some slight adjustments as you tow if you don not wish to feel this..

To some folks the grabby feel is acceptable and some folks the grabby feel drives them crazy..

It is the reason I skipped those types of controllers and used Jordan Ultima 2020 controllers until I got a vehicle with IBC.

OP will need to find a compromise in settings that still gives decent braking but not as much low speed grab..

wowens79 wrote:

Is this normal, and something I just need to get used to?

Yes I think so.....mostly.

But at parking lot speeds, there is little or no need to have brakes on the trailer at all under normal circumstances.
So if you can easily turn them off, do that.
Just turn them back on when leaving the low speed area.

Or just live with the jerkiness.

New brakes is the problem. Trailer brakes don't work all that great until they have quite a few start / stop cycles on them. In other words, they need to be burned in.

I did RV transport for 2 years. I ALWAYS had to run my brake controller at max setting to get much braking action for the first part of the trip. By the time i reached my destination 224 miles later, the brakes were working better, but just barely, because the trip didn't involve much stopping and starting.