Join Date: Jul 2007
Location: Truckee, CA
Thanked 116 Times in 114 Posts
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Re: rebuilding a trailer
I had two trailers with surge/drum brakes, one about 2,000 lbs the other about 6,000 lbs.
It was always kind of hard to tell how they were working. Once in a while, conditions permitting, I would get on the brakes really hard. To the best of my observations I never smoked the tires on the truck or trailer and everything stayed straight and stopped about the same as the truck alone.
You can block the trailer wheels and have someone reverse the car and then watch the coupling to make sure the surge linkage is operating full travel. Another way to test them is to back up a fairly steep grand without the reverse interlock operated. You should feel a fair amount of resistance.
If the master cylinder is full and the shoe linings show signs of fresh contact with the drums or discs they are probably working.
I would suggest:
1. Find a commercially designed and made trailer factory equipped with brakes. Make sure it is certified to carry your weight
2. Completely inspect and test the brakes.
3. Replace/ refurbish brake components as necessary, in addition to the bearings and races.
4. Carefully inspect all welds and/or joints
If you decide to build one yourself, design is critical. Buying a set of plans from an established commercial fabricator would be worth the money, in my opinion