Originally Posted by mward3
The truck I have now is a Ford F350 with the tow package built in. Also it has an electric brake control in it. If it has tow control why does it need a brake control?
The newer Ford SuperDuty pickups have some electronic gizmos that assist with trailer sway, but that has nothing to do with stopping the rig using the brakes on the trailer and the tow vehicle. You need the brake controller to activate the electric trailer brakes. The optional Ford trailer brake controller is a really good one, compared to some of the less sophisticated versions available on the aftermarket.
The brakes on your truck are designed to stop the truck when loaded for bear, but they are not intended to also stop the trailer. That's why trailers have brakes. But you have to tell the trailer brakes when and how much to brake the forward progress of the trailer. You talk to the trailer brakes through the trailer brake controller in the truck.
The more electric "juice" you send to the trailer brakes, the more the brakes will clamp onto the brake drums of the trailer axles. The electric trailer brakes use magnets to push the brake shoes against the brake drums, and the more juice to apply to the magnets, the more braking force you have. Too much juice and the trailer brakes lock up and lose traction, which not a good. Your Ford trailer brake controller sends juice to the trailer brakes depending on how hard you mash on the brake pedal. So it is called a proportional brake controller - the harder you mash on the brake pedal the more juice is sent to the trailer brakes. Most trailer brake controllers send a fixed amount of juice to the brakes, and you must adjust the brake controller to tell it how much juice to send depending on the weight of the trailer. But the Ford trailer brake controller is "integrated" into the Ford brake system, so it sends about the same braking force to the trailer brakes as the brakes on the pickup are using.
I'm sure the above description can be improved upon, but I'll let others do it.
My new pickup has the optional Ford brake controller. I took the rig out yesterday, drove 30 miles to a CAT scale, and weighed the rig. The trailer brake controller worked great on that 60-mile round trip.
Some expensive new trailers have "electric over hydraulic" disk brakes. The trailer brakes are disk brakes just like the disk brakes on your truck, and they are activated by brake fluid (hydraulic fluid) just like the brakes on your truck. But instead of having a brake pedal to mash on the master cylinder, they have an electric connection to a solonoid that mashes on the trailer's master cylinder when you send juice to the trailer brakes. Your Ford integrated brake controller should work on electric over hydraulic brakes as well as ordinary electric trailer brakes, whereas most brake controllers will not work with electric over hydraulic brakes.