Trailer Brake Magnets Not Making Full Contact with Inside of Brake Drum

Updated 07/28/2015 | Published 07/26/2015

Question:

My question now is how much of the Dexter magnet must contact the machined face inside my hubs for the brakes to be effective? My Hadco hubs have an inside magnet mating surface diameter of 8 1/2inch which permits your recommended Dexter brake assembly magnet to contact with all but about 3/4inch of it touching the mating face. Is this enough to properly activate the brakes? Please advise, thanks.

asked by: Ray K

Expert Reply:

The brakes should still work fairly well. The magnets, when energized, cling to the armature surface of the drum and the rotations of the drum pull the magnet which then pushes out the shoes to make contact with the drum. If the brakes seem weak then you could adjust them out to be a little more aggressive to compensate for the little bit of the magnet not making contact with the drum. And if that still is not enough then you would need to replace the drums.

expert reply by: Michael H