Rear trailer brakes overheating

[Ole Orange]

Another question? when I slowly step on the brakes I always see the full output on the digital controller, if I set it to 7.0 then when I touch the brakes it says 7.0 is this correct? seems to me it would have to be this way as its hooked to the brake lite wire I think

 

[Diamondpilot]

You said you hooked color to color when you installed the controller..... This may be your issue.

Many many times it's not color to color and for example red does not always equal 12 volt input.

On most controllers Black is 12V pos.
White is 12V neg.
Red is brake light signal.
Blue is controller output to the trailer.

You will have 4 wires usually on the controller. Red, black, white, blue. Not sure what your older Dodge has on its end but don't worry about color, worry about function.

It's something to check but weird it's still only heating up the rears unless the fronts have weak magnets.

Here is a good link for Dodges.
Dodge Truck brake control install

Chris

 

[oldballs]

Do they get hot if you pull the plug / connector and tow it? That would separate mechanical / trailer issue from electrical / tow vehicle issue.

That, too, sounds like a good way to separate it out.

 

[oldballs]

I just want to follow the thread because I had presumed hot wheels on my camper.

How hot is too hot? Can you hold your hand on the wheels? Maybe that is normal and something is wrong with the cool fronts.

My experience with a dragging shoe, was that the normal hubs were at the surrounding air temperature, whereas the dragging shoe made that hub warmer than all the rest....although not as hot as the OP's. I just felt it with my hand, no fancy instrument.

 

[3930dave]

Another question? when I slowly step on the brakes I always see the full output on the digital controller, if I set it to 7.0 then when I touch the brakes it says 7.0 is this correct? seems to me it would have to be this way as its hooked to the brake lite wire I think

As Chris laid out, Brake Light signal is a separate wire at the controller.

Display reporting on a digital controller I can't comment on, as I have an old analog controller on mine. AFAIK, all controllers have to be able to send a variable DC voltage to the trailer brake magnets - to avoid overbraking or heat problems. On my old analog controller, I have a big slider pot that I can use to manually apply just the trailer brakes, and a smaller slider pot that sets the magnet voltage when I use the tow vehicle brakes. On mine, you can jack up the trailer, test with 2 people, and feel the difference in braking level on the trailer as you change the controller settings.

From memory, I think the minimum setting on mine was something like 6 or 7 volts on the trailer magnet wire.

A modern trailer brake controller will sense motion - the faster the tow vehicle is braking, the higher the voltage will probably be on the magnet wire. You'll have to read your controller manual, to see exactly how to test it's output when the vehicle is parked, and what to expect on the road.

I'd first verify all your wiring, making sure that the magnets are not being fed from the Brake Light wire. Then test magnet voltage parked, as per the brake controller manual. If you have a DMM that logs Min/Max DC, connect that to each magnet line in turn. Take the trailer for a drive - I want to think that on the lower controller settings, you should see a reduced Max DC voltage on a test drive - but that's only a guess, as I haven't played with one of these new controllers yet.

Rgds, D.

 

[Ole Orange]

Well looks like I have another weekend project laid out for myself.
my first is to hook on and disconnect the rear axel brakes all together and take a short 10 mile trip.
I just downloaded the book for the controller and will go through that as well.
I checked the back plates last night and can not find any marks for left and right, my plan is to pull both hubs and see if all works and if front and back match.

Thanks for all the input
this one is a mystery to me???

 

[hosspuller]

Well looks like I have another weekend project laid out for myself.
my first is to hook on and disconnect the rear axel brakes all together and take a short 10 mile trip.
I just downloaded the book for the controller and will go through that as well.
I checked the back plates last night and can not find any marks for left and right, my plan is to pull both hubs and see if all works and if front and back match.

Thanks for all the input
this one is a mystery to me???

When you pull the hubs ... look at the brake actuating lever. It should be on the leading side of the wheel. And the magnet hanging down. If the magnet is at the top, the assembly was installed upside down. The magnet weight alone will keep the brake engaged.

See this page for the differences left / right Dexter Axle - Trailer Axles and Running Gear Components - 10" Brake Assemblies

 

[3930dave]

Well looks like I have another weekend project laid out for myself.
my first is to hook on and disconnect the rear axel brakes all together and take a short 10 mile trip.
I just downloaded the book for the controller and will go through that as well.
I checked the back plates last night and can not find any marks for left and right, my plan is to pull both hubs and see if all works and if front and back match.

Thanks for all the input
this one is a mystery to me???

On the Dexter brake assemblies I bought about a year ago, Left or Right was stamped on the inside face of the backing plate - you may be able to see it on yours with the drums pulled off.

Rgds, D.

 

[Ole Orange]

When you pull the hubs ... look at the brake actuating lever. It should be on the leading side of the wheel. And the magnet hanging down. If the magnet is at the top, the assembly was installed upside down. The magnet weight alone will keep the brake engaged.

See this page for the differences left / right Dexter Axle - Trailer Axles and Running Gear Components - 10" Brake Assemblies

Thanks for the site with pics I will compare tonight when I pull a couple of hubs. Pretty sure the magnets are down as the adjuster is at the bottom on all 4 back plates but do not know if the levers are forward or not.
It seems to me if they mounted the rears wrong they both would be wrong left on right and right on left.
I am going to pull the hubs tonight and check I will post what I find.

 

[Ole Orange]

Well I pulled all 4 hubs off and magnets are all down, right side has right brakes and left has left.
levers are forward and the rears are full of brake dust that must show they are dragging.
my electronic controller directions says it will indicate any shorts etc. but checked anyways and found none. the controller was set at the most aggressive setting so backed it off. for what ever reason the rears seem more aggressive than the fronts so I backed the thumb wheels off on the rears some even though they seemed ok.
Had my wife run the controller all 4 release when she lets go. did not get to tow it last night as pitch black when I was done. will keep trying.
ps it is an electronic Draw-tite controller