How do you adjust your Brake Controler

[Keith Wire]

Mark,

I do not run with any boost.

Keith

[Mr. Adventure]

Originally Posted by Keith Wire

Hi all,

So the question is, how do you adjust your controller? Is there a proven way, or do we all just have to guess; then hope and pray we have it right?

Thanks, Keith

The best way is to follow the manual. After that, we all have to guess, and then hope and pray we have it right.

I'd like to believe the trailer axle would do it's own stopping. But without anti-lock brakes and given the guessing the controller has to do to understand what's going on, I figure the trailer will only actually do about 2/3 of it's own braking. This means that when towing in the best of circumstances, we still need to allow better following distances and drive at slower speeds to compensate. And it's always in the back of my mind that my TrailManor came from the factory with wire nuts on the brake wires .

No boost here either. IIRC the manual recommended boost only for heavier trailers.

And what Mr. Adventure says is so true. "Theoretically" the trailer brakes should stop the trailer. That's the assumption behind my Tacoma's 6500# tow capacity. And unfortunately, if that's not the case I cannot necessarily rely on my TV's brakes because it's GVW is pretty well maxed out (>= GVWR).

So you just have to be really paranoid about your trailer brakes. Make sure *both* are working and adjusted properly.

There may also be better controllers out there than the prodigy, but I don't know which. In particular, I would like one that measures current so you can tell if both brakes are working. And one with better or adjustable brake timing/synchronization. Currently at high settings (>7), the trailer brakes come on much sooner and harder than the truck brakes, making for very jerky action at low speeds.

Originally Posted by brulaz

IIRC the manual recommended boost only for heavier trailers.

Not technically true, see attached. It loosely defines which boost setting to use by comparing TV weight to trailer weight. With my Tundra, either ".c" or "b.1" settings are suggested. If I were to tow with my Sienna again, ".c", "b.1", "b.2" settings are suggested. (Using 4000 lbs as TM weight)

[rickst29]

Originally Posted by Mr. Adventure

I'd like to believe the trailer axle would do it's own stopping. But... I figure the trailer will only actually do about 2/3 of it's own braking....

If you've got 1/3 of the Trailer braking coming from the Tow Vehicle, you need to turn your current value up-- a lot. I hope that I misinterpreted your post, but it sound as if you've got 1/3 of the braking action for the Trailer coming from the TV brakes, through the hitch. If so, that's dangerous and wrong: The Trailer pushing forwards on the TV, while the "stronger" TV brakes are resisting the push, is recipe for skid.

That's a skid of the entire Trailer versus the TV, not just the TV rear axle. Now think about that for a moment: If you see the rear of your Trailer trying to "catch up" with you, along the side of your TV, you're almost certainly headed for the ditch! The only way out is to speed up strongly, turn the front of your TV to the side where the rear of the Trailer is going.

You need to have the Trailer "pulling" the Trailer back under all braking conditions, because that keeps the hitch in line. EVER have the Trailer pushing the TV! The Trailer brakes need to be slightly stronger: At a given brake pedal position, the Trailer has slightly shorter stopping distance than the TV. (if it could maintain exactly that amount of braking while disconnected from the TV.)
-----
That's why you MUST feel a bit of "pull", and never any "push". But per that post I wrote in the other Thread, I think that Prodigy's advice doesn't work in slick road conditions- they tell you to set the controller "just short of lock-up" on DRY pavement. That can be too much braking power, if the TV's antilock engages before a Trailer wheel begins to spin; or, it can be a disaster-- if one of the Trailer wheels starts spinning, and the whole thing starts to skid.

Like TM's advice to "ALWAYS" fill the tire to maximum pressure shown on the sidewall (which have been inspired by the Firestone lawsuits and bankruptcy), Prodigy's advice is legally safer for them, but IMO not optimal for you unless you avoid towing in rain and snow. In addition to skids provoked by a spinning tire, it can cause the Trailer to pull your TV out of line on a curve. For example: Think of braking on a downhill switch, when your TV is already most of the way through the turn-- but your Trailer isn't. Under Mr. Adventure's scheme, the Trailer has only about 2/3 of the braking it needs -- so it tries to go straight (over the cliff and through the woods, to Grandmother's house.... dragging your TV with it). Under Prodigy's scheme, the Trailer stops really fast and hard-- but your TV is still moving quite a bit, SIDEWAYS relative to the "parked" Trailer. This is not a good situation, IMO. Hitch components could be broken, and maybe one of the two vehicles could be flipped on it's side. (The Trailer would flip to the "inside" of the switchback curve; the TV would fall towards the outside, and possibly go down the hill as a result.)
- - - - -
Answering a question above, my 4Runner and 2619 are well-matched with setting "B.7"

[Mr. Adventure]

Originally Posted by rickst29

...I hope that I misinterpreted your post...

I'm pointing out the weaknesses in trailer brakes and controllers as a reason for caution while towing. Anyone thinking they are going to do a panic stop while towing in the same distance as their solo tow vehicle with its computer controlled anti-lock braking system is mistaken, though admittedly by an amount that's pretty hard to determine without actual measurements.

I get this by the following logic:
1) The point of maximum braking is infinitesimally short of a skid because static friction is greater than dynamic friction. Your tow vehicle's anti-lock brakes know how to find this point independently for each of your four tow vehicle tires, but your trailer has no similar features.
2) Even without anti-lock brakes on the TV, you'd have enough braking capacity to lock all four of your tow vehicle tires. With your trailer brake controller at maximum, you probably can't lock the trailer tires on dry pavement (don't try this in traffic). Therefore, your trailer is not equipped with the same braking capacity at each wheel as your tow vehicle.
3) You don't want your trailer brakes to lock, ever. A skidding trailer behind your better-braking tow vehicle would try to pass you. Therefore a trailer braking system that is not able to lock up the wheels is a feature, not a bug, as we used to say in the software business.
4) Not all road surfaces provide the same traction. There are bigger braking problems on slipperier surfaces.

Therefore, even the smartest available brake controller can't make our trailer brakes completely do their share. The controller can make the trailer brakes start earlier and manage themselves through the stop. But, the trailer system has to be compromised enough so that the trailer doesn't lock up on a wet road (you might not have time to readjust the controller settings while you're concentrating on a rainy panic stop).

My proposed rule of thumb would be that your tow vehicle routinely has to stop itself plus 1/3 of the trailer's weight not just because your tow vehicle is carrying a good chunk of it on the tongue but also because your tow vehicle is also a substantially better stopper than your trailer. Your stopping distance will accordingly be longer.

Is a longer stopping distance unsafe? Yes, when you are going too fast for your vehicle, load, and conditions. Absolutely, when it's longer than the distance to the problem in front of you.

Originally Posted by M&M Hokie

Not technically true, see attached. It loosely defines which boost setting to use by comparing TV weight to trailer weight. With my Tundra, either ".c" or "b.1" settings are suggested.

Ah yes, thanks. Same with my Tacoma.

Guess I never tried the b.1 setting because the trailer brakes already come on earlier than the TV brakes at high (non-boost) settings, making for very jerky operation at low speeds. Wish that timing part could be adjusted better, perhaps if it were speed sensitive?

Or maybe I should try reducing the numeric value down some from 8 and using b.1 instead of .c ? Hmmmm ...

I have a Prodigy P2 and my brakes don't lock up. I'm sure they are in need of adjustment because I have not had them apart yet. On the highway I run mine on as high as they go, 12 with no boost. Seems to work well and no lockup. I had an emergency stop at over 70mph with my abs engaging because the cars in front of me slammed their brakes. I must say my rig stopped on a dime, I couldn't even tell I had the loaded down trailer behind me. The guy behind me with his F350 and triple axle fifth wheel had to bail to the dirt median, luckily it was their or my rig would have been toast.

On city driving I cut it back to about 7 or 8 to smooth it out. Also on steep declines I cut it back because the trailer brakes seem to heat up really quickly compared to my truck brakes.

[Mr. Adventure]

Originally Posted by joshbw

I have a Prodigy P2 and my brakes don't lock up. I'm sure they are in need of adjustment because I have not had them apart yet. On the highway I run mine on as high as they go, 12 with no boost. Seems to work well and no lockup. I had an emergency stop at over 70mph with my abs engaging because the cars in front of me slammed their brakes. I must say my rig stopped on a dime, I couldn't even tell I had the loaded down trailer behind me. The guy behind me with his F350 and triple axle fifth wheel had to bail to the dirt median, luckily it was their or my rig would have been toast.

On city driving I cut it back to about 7 or 8 to smooth it out. Also on steep declines I cut it back because the trailer brakes seem to heat up really quickly compared to my truck brakes.

Trailer brakes could heat up too quickly in long downhill stretches when the controller setting is cranked all the way to 12 because the trailer is doing too much of the braking for too long, and you could be cooking the trailer brakes. In effect, you're asking the trailer to do more of the routine braking.

In a panic stop, you probably would get more braking out of the trailer that way, but you're also at higher risk of a trailer brake lockup on wet pavement (you can manually do the same thing by applying the lever on the controller). Of course, you'll still have a longer stopping distance than if you weren't towing.

I've always thought this adventure in the thread that follows was caused by an overly aggressive trailer brake setting:
http://www.trailmanorowners.com/foru...ght=bolt+wheel

I see your point but the prodigy manual states to set your controller to the point where your brakes are about to lock up. At 12 my brakes will not lock so how is this too aggressive? This is just my take and I'm not a brake expert.

If its wet the controller setting most definitely reduces to about 8.