Parts Needed for Converting Trailer from Hydraulic Drum to Electric Drum Brakes

Question:

I am going to retrofit a trailer that currently has 4 wheeled, hydraulic brakes with electric brakes. Will the 10inch Nev-R-Adjust Electric Brake Assembly for 3.5K Axlesinch work with Trailer Hub and Drum Assembly - 3,500-lb Axles - 10inch Diameter - 5 on 5-1/2inch or would you recommend something else? I have 12 inch wheels with a 5 on 5-1/2 rim bolt pattern.

asked by: Tyler W

Expert Reply:

Your wheels' 5-on-5-1/2 bolt pattern does not affect the fit of electric drum brake assemblies, but the bolt pattern on the brake mounting flange does matter, as do the diameter and width of the hubs/drums, and your axle rating. You'll want to confirm the mounting bolt pattern on the brake flanges to ensure you choose new electric brakes that will bolt up; check the sticker on the axle to find its weight rating and measure the diameter and thickness of your current hubs/drums to find their size. Please see the photo I linked for you.

Without knowing your existing hubs I cannot be sure they will work with the new brakes. Your best bet is to find the hub's bearing numbers and with those I can help you select compatible hubs.

Also, the comprehensive article linked for you will give you all the information you need for the conversion from hydraulic to electric drum brakes. Our main page for electric trailer drum brakes is also linked. You can click on the filters on the page to select your axle rating, drum size and brake type - manual-adjust or self-adjust.

You will also need a brake controller like the outstanding Prodigy P2 # 90885 which will slow the trailer in direct proportion to the rate the tow vehicle slows down.

The type of brake controller installation you'll do, plug-in or hardwired, depends on the vehicle year/make/model and how it came equipped from the factory. Some vehicles will have a quick-connect port under the dash that makes controller installation as simple as plugging in two connectors, while others will require some wiring work. If your vehicle is a 1998 Dodge Ram with a factory 7-way then to install the Prodigy controller all you'll need is the harness # 3020-P.

If your trailer has a surge coupler like # DM72VR you will need to either replace it with a standard coupler or drill a hole through it sideways to allow installation of a bolt that will immobilize it. The existing brake lines on the trailer will not be needed so they can be removed or left in place if you prefer.