Rear Trailer Brakes are Weaker than Front Trailer Brakes on a 2007 Horse Trailer

Question:

Trailer is a 2007-model CM 16-ft. horse trailer. This trailer has 12inch drums on all 4 wheels. I have put in a new junction box, new connector plug, removed the drums and inspected the shoes and magnets, front and rear. The manufacturer used 14-gauge wire for the brakes, run back to the left side of the trailer. This wire then splits to the left front and left rear brakes. The right side brake wiring is spliced in on the back of each left drum with 16-gauge wire strung through the hollow torsion axles. I have re-done the splice points, and I feel sure the ground connection is solid. The left and right FRONT brakes operate normally and will lock up on gravel. The left and right REARS are very weak and dont contribute much to stopping. In fact with the wheels off the ground and someone stepping on the tow vehicles brake pedal, I can barely turn the rears by hand. There is some braking action, but not enough. All 4 wheels have been adjusted identically, so Im stumped. Is it the 16-gauge wiring?

asked by: Neal A

Expert Reply:

Chances are that the smaller gauge wiring is not causing the problem especially since it is not so long as to offer much resistance. But, you can certainly try a larger gauge.

I would still check those grounds because a weak ground can cause all sorts of problems. Just make sure that they are attached to clean and corrosion free metal surfaces that are not painted. Having a short ground wire would be beneficial.

You can test to see how much voltage is getting to the magnets with a multimeter and if it is the proper amount then the brakes either need to be adjusted more or the magnets themselves need to be tested further.

You can visually inspect the magnets but to test them thoroughly you will need to use a multimeter like # PT89ZR if needed. I have incldued a link to an FAQ that covers how to test the magnets.

expert reply by: Michael H