Ineffective Braking on Car Hauler Trailer Towed By 2008 Lincoln Navigator

Updated 07/11/2012 | Published 07/09/2012

Question:

I bought a car hauler trailer with one axle electric brakes. I want to make a long trip so I replaced the brakes completely. New controller in my navigator. The trailer has new backing plates with all new parts complete and new drums. The brakes apply but not with very much braking force. If I set the controller manual adjustment to 100, even with the wheels on grass the brake axle will not lock up and not much force or braking effort it works, but not as much as I think that it should. Grounds are all good new holes and bolts. The brake wireblue looks to be about 14 or 16 gauge. Could this small wire not let enough amperage and voltage get to the magnets and cause a problem like what I have explained or should I look at something else? Thank you

asked by: George K

Expert Reply:

There are a few things that could be causing your trailer brakes to preform poorly.

As a start, make sure your trailer is not overloaded. If it is a 2 axle trailer with brakes only on one axle, you might consider adding brakes to the second axle. Even though the weight carried on the trailer might not be exceeding the trailer axle capacity, one braking axle might not be enough to efficiently stop the trailer when it is loaded.

It is possible that your brake output wire is of too small of a gauge. I would consider anything smaller than 12 gauge as being insufficient.

When you replaced your brakes, did you adjust them? Remove the adjuster hole cover from the rear of the brake assembly, and use a screwdriver or brake adjustment tool (available from your auto parts store) to tighten the adjusting wheel until the trailer wheel is very difficult to rotate. Then, back off the adjustment wheel 10 or so clicks, or until there is a slight drag. Repeat this procedure on each brake assembly.

I would also recommend reviewing the set-up procedure outlined in the instructions for your brake controller, so you can rule that out.

If these possible causes all check out as okay, please get back with me and we will check some other less common possibilities.

expert reply by: Mike L