Trailer brakes - basic questions

[GaryM]

Tow package usually gets you stuff that's hard or expensive to add on later. It varies with manufacturer and model but I've seen the following on tow packages:

Bigger brakes
Added or bigger transmission cooler
Bigger radiator
Bigger alternator
Variable load flasher
Heavy duty shocks
Wiring for the trailer, including the controller connector and wiring to the back of the vehicle
Plus the receiver.

A pretty good deal for the $150 or so they usually charge.

[robertn]

I'd get the controller. Mine works well(Tekonsha Sentinel) and only cost like $80-90. Small price to have additional safety for the $30k truck, $15k tractor, and $2k trailer. What's $100 compared to a $47,000 package. In my case, if you count it that way, I'm at $53k...

As others have mentioned, that tow package gets you lots of heavy duty upgrades. It is like my pet peeve about lack of hook in pickup beds; there are lots of brake controllers, for 2-4 axles and different types of controls.

I wish the factories did carry a brake controller. It would be real sweet to have one in the dash. I even have a spot for one. I hate that bolt under the dash catch your shin on kinda stuff.

Oh, as someone else mentioned, you don't have to wire the whole truck! I had to wire one a few years ago. It was not real hard, but it sure was a pian compared to what you truck has, all prewired and all.

[Pat]

I have the same controller (Tek) and it works well. You do need to turn it up when trailer is loaded and down when not but that is not hard and takes about 5 seconds to set a few times by experiment. Controller will slide the tires if you forget to turn it down after unloading the trailer. What next a wheel rotation sensor that prevents locking up a trailer wheel?

Between my Dodge truck, $2000 trailer, and Kubota I have over $80,000 (new cost) at stake and don't ever consider not having a controller and a breakaway brake setup with remote battery.

Pat

[Inspector507]

Pat,
An ABS system for trailers?? I like it.. [img]/forums/images/icons/grin.gif[/img]

[Chillimau]

Vehicles and equipment are cheap compared to personal injuries.

Gary

[Pat]

Trailer ABS... Maybe I'm just lazy and or forgetful but I think it would be neat if I didn't have to adjust braking force to avoid lockup when unloaded. Getting independent measures of the rotational speed of the wheels is not difficult or expensive. The electronics to modulate the brake application current to avoid lockup is NOT COMPLICATED. If mass produced, a DIY installation per my guestimate should come in around $75 per wheel but could be significantly less if manufactured in large numbers.

Such a system would not let any wheel get way slower than any other due to brake force and would not allow any wheel to lockup. Should be easily expandable from 1 to 6 or more wheels.

pat

[Davidj]

You're right, it wouldn't be difficult but it would basically be putting a controller on each wheel so that the wheels that weren't skidding would keep braking at maximum. I still like the idea of ABS on the towed vehicle.

A better approach to the current situation might be a strain gauge (weigh cell) on one of the axles or on the tongue to indicate an unloaded trailer and bias the controller automatically.

[Pat]

David, Actually the controller would have a series pass device to limit current to skidding wheel to prevent lockup. This would not give the non skidding wheels max breaking force but would give them 100% of whatever the standard controller called for.

The distinct advantage over just measuring weight and factoring that into the control equation is that approach could not compensate for differences in traction or imbalances in loading the trailer (or stock walking around in it.) What I suggest would not lock a wheel even if one wheel was on dry pavement, one was on wet grass, one was on cow flop, and another was in the air from a bump. Each would give as much of the controller requested braking as it could without lockup, whatever that was.

I suspect some sensor, like two coils of wire at right angles to each other placed near the wheel with one as exciter and one as detector could easily determine angular velocity. Alternatively, small magnets could be attached to the rim like wheel weights and a coil would detect their passing. If the wheel stops rotating there would be no more pulses detected from the magnets passing and the control circuit could reduce braking effect until pulses were restored. I'm sure someone with talent and recent EE experience could prototype something like this in just a few hours.

Pat [img]/forums/images/icons/smile.gif[/img]

[Davidj]

Thanks for hitting the jog button. [img]/forums/images/icons/grin.gif[/img]

I thought of a simple solution for an in place controller. Place a small proximity sensor on each wheel and let it control a sealed relay in series with the brake coil and simply disconnect the coil upon rotation cease. A snubber will be needed because of the pumping effect this will potentially create. This would be a easy application to try and would be very robust.

The reference to the strain gauge was simply in response to not wanting to manually readjust the sensitivity of the controller when the trailer was unloaded. I know I made it over simplistic but was just throwing out ideas.

[Hank]

<font color="purple"> I guess I'll bite the bullet and pay the $150. </font color>

I have the prodigy as well, but shopping around can get you a lot better price. At this place it's only $118