Adding Brakes To A 2004 U-Haul Tow Dolly

Question:

I purchased a retired 2004 Uhaul tow dolly that was manufactured by Demco. It does not have brakes and I was wondering if there is a way to add brakes to the trailer like surge brakes? I believe the axle capacity is 3,450 lbs and it has 14 inch wheels the tore size is 205/75R14.

asked by: Dan V

Expert Reply:

In order to add brakes to your tow dolly you'd first need to have a brake flange for the brake assembly to mount to. If you remove the wheel you'll be able to see the if there's a brake flange, like you can see on part # TRU74FR, or not. If not, you can get them welded onto the axle but the cost typically exceeds the cost of just replacing an axle because the weld has to be so precise.

From there you would need to determine if you want to go with hydraulic or electric brake assemblies. If you go with hydraulic you'll most likely need to replace the coupler with a surge coupler and would need to run hard brake lines from the coupler out close to the brake assemblies and then use soft flexible lines to complete the connection. You'll need new hub/drum assemblies that match your wheel bolt pattern as well.

If you want electric brakes you'll need to install a 7-way and junction box, run 10 gauge wire out to the brake assemblies, replace the hub/drums to match the wheel bolt pattern, install a breakaway switch and breakaway battery, and the tow vehicle would need to have a brake controller and 7-way connector.

I've attached two guides below that go over adding electric or hydraulic brakes to your dolly that offer diagrams to make this easier to understand but I'd still be happy to help if you can determine what brake type you'd like to go with, if there's a brake flange, the bolt pattern for the wheels, and measurements B, C, and D on the diagram below so that I can find a hub/drum assembly with matching bearings to your axle's spindle.

expert reply by: Kevin C