Brake Controller?

[Jay D.]

my 2010 gmc had the integrated brake system, i liked it but it started doing strange things finally it would only work intermittently. i did a LOT of research on how to fix it to no avail. found out its very common. a couple dealers told me they couldn't fix it. unless i wanted to dump a couple thousand in new computers in it. SO i bought a REDARC it seems to work real good and easy to install.
Jay D.

[1320Fastback]

Originally Posted by LenR

Add on controllers for many years now have not been allowed by highway safety regulations to tap into the vehicle brake hydraulic line to monitor brake petal push.

My daily driver and tow pig still uses a Kelsey Hayes hydraulic controller tapped into the rear brakes at the master cylinder. While not the safest in theory it is the smoothest trailer brake controller I have ever used.
I believe the issue that led to them being banned was their required volume of fluid was more than some systems could supply which led to decreased braking power.

[Dave Pelletier]

A long time ago in a galaxy far, far away, I wrote an article on brake controllers when I worked in the automotive industry. I don't have it anymore but a google search reveals a surprising lack of information as well as a number of errors. I haven't kept up on developments in recent years but;

- Most sources will tell you that there are two types of electric brake controllers (surge hydraulics being a different system entirely); Time delay and Proportional.

Time delay controllers are the cheapest and least effective controllers relying on a preset voltage and adjustable time delay to activate your trailer brakes - they have no way of knowing whether you are just lightly applying the brakes or are in a full on panic stop so, as you might imagine, they are jerky and not that effective supplying too much braking during light brake pedal activation and not enough during heavy activation.

The Proportional controllers operate several different ways;

- cheapest and least effective are the inertial/pendulum ones that have a weighted pendulum that moves when the TV slows down activating the trailer brakes; the more brakes you use on the TV, the more the combo slows, the more the switch applies braking voltage. The problem is that you first have to slow the truck and trailer using the truck brakes only in order to activate the switch! Much better than time delay units but far from ideal.

- next Proportional based controller uses actual TV pedal POSITION to determine how much voltage to send to the trailer brakes; these require a complex linkage and setup though they can offer decent proportional braking. I'm not sure these are even used anymore.

- finally, the best Proportional system uses a sensor to sense hydraulic brake pressure in the TV; once these have been setup properly, the controller modulates the trailer brakes based on how much TV brake pressure is applied making them the best and most seamless type of controller. Originally these were problematic in the fact that they required you to physically tap into the TV's hydraulic braking system which could cause leaks and, in the worst case, problems with the TV's brakes. This would be the type 1320Fastback is referring to. I believe all current OEM brake controllers are hydraulic pressure based.

Until we started seeing OEM brake controllers, almost all were time delay or pendulum inertial controllers.

2 cents,
Dave

[carybosse]

My fine tuning probably does not meet any standards.

First, I make sure the system will manually activate the brakes, even to the point of locking up the brakes in manual with no truck brakes applied. I then try it out at slow speeds to see if I can get a smooth stop with a smooth braking on my part, not an emergency stop.

Once I feel comfortable with the setup, I head out. If it seems to jerky on stops, I may back off a notch on the setting. If I feel like the trailer is pushing me, I take it up a notch.

Pulling a trailer, I try to make sure I never put myself in a position where I really need to be concerned with the trailer brakes. My eyes are focused on immediately in front of me, but also several hundred feet in front of me. There are too many idiots on the road who have no concern with pulling out in front of an RV, not a concern in the world we may have longer stopping distances. People who would never pull out in front of a commercial vehicle will pull out in front of an RV setup that has 8 wheels and is 50-60 foot in length and may be running 15-30K pounds of combined weight. (the diesel pushers with a toad could be much worse.)