Brake Controller Adjustments

It might help you a bit to take a look at this thread, which is a sticky in the Towing forum, about adjusting your trailer brakes and checking wheel bearings. It has detailed instructions, complete with close up pictures, and was done by our resident guru JBarca.
Barney

westend wrote:
First, the trailer battery does not power the brake system when in ordinary use, only when the emergency break-away switch is activated.

If your wheels aren't locking on the trailer it may be that they need inspection and adjustment on the trailer. That would be SOP when I buy a trailer, especially one that has been used since I would have no idea about previous use or maintenance.

X2. If the maintenance history is unknown, the trailer brake adjustment would be the first thing to consider.

Copied from Frequently Asked Questions on the Dexter Axle web site, the manufacture of most trailer brakes.

" BRAKES - Why can't I lock and slide my electric brakes?
On an unloaded trailer, you may be able to lock up your brakes if your electric brake controller is supplying full amperage to the brakes. When loaded to capacity, you may not be able to lock your brakes as electric brakes are designed to slow the trailer at a controlled rate, and not designed to lock up the wheels on a fully loaded trailer. Our brakes are designed to meet all applicable safety standards. All of our brakes will perform better after numerous burnish stops to seat the brake linings to the drums."

brulaz - that is part of my concern. As it is I have no room to adjust upwards.
If I get into a situation where I need more braking power, I'll be U.S.C.

Still listening to all of your responses. Very helpful to give me an idea how these brakes work. Just checked the output to the trailer and it shows 12v, so the controller seems to be working as it should. I will have the TT brakes checked and adjusted as needed and go from there. I know there is moderate braking on the trailer....just not sure how much it should be because I'm new to this. All of your comments are helpful. Thanks

Not using a Prodigy, but similar problem.

New trailer, couldn't get brakes to lock up when adjusting.
Six months later I adjusted them and they were way loose.
Afterwards they locked up at 8/10 (before I had it at 10/10 and no lockup), so I set the controller at 7.5/10.

This is a heavy 7500# trailer with two 5200# axles and 12" drum brakes.

One more thing: brake temperature changes everything. You're supposed to warm the brakes up a bit before adjusting the controller but not let them get too hot. I think the idea is that under normal operation, the brakes will be cold/warm. And when you make an emergency stop under those conditions, you will then get maximum trailer braking, not lockup.

But as I recently discovered, that may not be the best controller setting when going down a long grade and when the trailer brakes get hot. In my case, with hot trailer brakes, I could increase the setting pretty much to the max without lockup. And it was useful to do so on a long grade. I also manually applied the trailer brakes separately to give the truck brakes a cool-down.

sllims wrote:
Sorry everybody. I'm still new at this.... Just saw the later postings.
It makes sense that I might not get them to lock. Prodigy should state this in their instructions. I do feel significant resistance. at 25mpg, the trailer alone stops both vehicles in about 30-50yds. I just did not think I should need to have gain at highest setting(12). Leaves no room for brake wear adjustment.

Brake wear is not compensated by gain. Gain adjusts power sent to brakes not brake linkage variances so don't worry about that. How does the combination drive/brake? Your brake gain should be adjusted so that it feels pretty much like normal braking without the trailer. You shouldn't need to set to max, if the trailer feels like it is stopping the truck under normal braking you have it set too high. With a heavy trailer I generally set the gain to B2 and 7.5 volts which works for most trailers. I don't use B3 except high speed interstate and switch to B1 when slow off normal roads

Sorry everybody. I'm still new at this.... Just saw the later postings.
It makes sense that I might not get them to lock. Prodigy should state this in their instructions. I do feel significant resistance. at 25mpg, the trailer alone stops both vehicles in about 30-50yds. I just did not think I should need to have gain at highest setting(12). Leaves no room for brake wear adjustment.

I had no boost on when doing the initial setup. Decided to but boost on B1 when I took it out on the road for the first time. But my understanding is this (B1) only increases the initial brake voltage, top end is still the same at 12v

BarneyS wrote:
Most larger trailers, like you have, will not lock up the wheels if you are on pavement. If you try it on sand or gravel you would probably get a different result. There is just too much weight and friction on the tires for them to lock up by the brakes on a travel trailer.

This is not to say that some people cannot get theirs to lock up. Some folks on here have reported that they can but I have never been able to, even when I just finish adjusting my brakes. This has been the result posted by most folks on the forums. If you can feel a strong pull back by the trailer when using the manual lever then I would not worry about it. I would, however, give the brakes an adjustment to make sure they are working correctly.
Barney

X2, I can't get any of my larger trailers to lock brakes like that, nor would I want too