Trailer brakes seem soft on new trailer

frugalangler · Jun 30, 2017

I acquired a new 'car hauler' for my new tractor, and it's the first electric brake trailer I've owned (every other trailer I own is is surge/disc). I've pulled them before, and have always used a good controller (Tekonsha P3) and and have been able to 'lock' up the brakes or come close when fully loaded.
I can monitor voltage and current to the brakes as a test. So, when I activate the brake manually with max power, I see about 13V and IIRC about 2A which I suspect is valid. What I don't experience is I can't
So, my question is: do drum brakes take some time to seat the shoes and become effective? I seem to remember years ago that was the case, but honestly it's been over 45 years since I last had any vehicle with drum brakes!

Without tearing them apart, I'm assuming there might even be an adjuster (or are they auto-adjust like automotive) that is accessible from the backing plate? I'm hoping someones experience might save me some time diagnosing a red hearing problem.

Thanks in advance.

George2615 · Jun 30, 2017

Welcome to TBN.....

I bought 2 trailers new in 2014 (Dump and a tilt bed). They are both 14K trailers and I believe when they were built the factory left the brake adjusters loose because I could not lock up the brakes manually. The adjusters are self adjusting but I didn't want to wait for the adjusters to take up the slack.
I raised the wheels off the ground and manually adjusted them through the backing plate till I could just hear the shoes drag when I spun the wheel. Brakes work as they should now and can lock up using the manual control lever or if my factory controller is set too high.

woody · Jun 30, 2017

yes there is a seating time, but if not properly set then the seating is not going to happen. what brand trailer is it and what are you pulling it with?

frugalangler · Jun 30, 2017

The brand is a Raptor, it's a 7K tandem single brake 16'+2' dovetail, I pull w/ a Jeep Grand Cherokee eco-Diesel (fitted w/ a Tekonsha Prodigy P3 brake controller) - the Jeep is a sleeper of a tow vehicle, unbelievable how well it does. And, with air-ride, it's a smooth go on my long haul trips w/ the bass boat!

I'm gonna lift each side and pull the brake wheel and see what the adjustment is/does, sounds like that's the culprit. I'll post back my results, thanks all for the info.

woody · Jun 30, 2017

while you have it jacked up spin the tire and let someone press the brake.

frugalangler · Jun 30, 2017

Well they were loose as a goose. I probably got 2 full rotations of the adjusters and it now will almost lock up. In time it will get better for sure but I now have brakes. Thanks for the feedback.

sidecarist · Jun 30, 2017

FYI most drum trailer brakes will only automatically adjust when backing up. From time to time while backing up use your controller to apply the brakes fully. This will keep them adjusted up and working g as well as possible.