Electric Trailer Brake Issues

[rmccallum98]

Hi all. Looking for some input and assistance.

Installed brand new pre assembled 5200lb drum brake assemblies on my trailer. Everything appears to be in the exact same location as the set that came off except for obviously new. My issue is when backing up my RH front brake makes a audible *clunk* after about 20ft the brake locks on and I can’t get it to free up unless I drag the trailer forward, the clunk happens again and we’re back in business.

Truck is a 02 F350 with aftermarket brake controller. From my inspections I could see the magnet arm would jam under one of the brake shoes with the drum off if I pulled it hard enough. But the arm would jam in the direction that would mean the trailer is moving forward. I took a die grinder and rounded the edge just enough to eliminate the hang up but the problem persists. Everything is tight and secure on the backing plate. The trailer will roll fine without the brakes applied but as soon as you touch the pedal and can hear the magnet energize you have about 4 rotations before the clunk and that drum is then very very tight and will remain frozen without any power or brake pedal applied. Really makes that tuned up 7.3 work to roll the trailer. Move the trailer 4 feet forward and it’s free.

I know it’s not an electrical issue, the magnet is not staying energized. It’s mechanical for sure but obviously can’t see through the drum or backing plate when the problem happens to see what’s going on. Any insight would be very appreciated!

[Old-Biscuit]

Did you perhaps install a Left Hand brake assembly on that Right Hand wheel position?

[rmccallum98]

Hi there I’ve installed LH on drivers and RH on passengers side

[MFL]

A possible cause, from Old-Biscuit above? The brake plate rear should be marked LH, or RH on the backside. Crawl under the trailer and look, making sure both axle brake plates are marked the same.