Parts Needed to Add Electric Drum Brakes to Second 3500-lb Axle of Tandem Trailer

Question:

I have a 20foot tandam axle utility trailer with 2-3500# axles. 1 axle has a brake on it. Can I add another brake assembly to the existing axle that doesnt have a brake and tie it in the wiring for the front axle that has a brake already. I should be able to, I believe. Ive got a email out to manufacture of the trailer, to find out the brand of axles I have on the trailer and the size of the existing brake assembly on the traile and the wheel size. I believe wheel size is 16. Or do I need to buy a axle with brakes installed on it. I believe I can convert axle with no brakes by buying 2 brake assemblies and installing and wiring them. thx in advance for the help.

asked by: Brian B

Expert Reply:

You can add electric drum brakes to your trailer's second axle. The second axle will need to have brake flanges in place or you will have to have a qualified welder with the right equipment (specialized jigs) weld them into place. Flanges must be installed perfectly concentric and level.

Since your axle capacity is known to be 3500-lbs odds are the brake assembly size for this rating is the 10 x 2-1/4-inch size. The linked page will show you all 10 x 2-1/4-inch electric drum brake assemblies. Brakes are handed - meaning there's a left and a right side part; be sure to order one of each for the axle. All the brakes shown use a 4-bolt mounting flange. I linked our page for 4-bolt flanges that fit these brakes. The linked article will give you excellent background and help you confirm the items you need.

Let's say you prefer self-adjusting brakes rather than the type you have to manually adjust yourself; in this case I suggest Dexter parts # 23-469 (right) and # 23-468 (left).

The brake assemblies have two wires. Either one can be affixed to the trailer for ground and the other to the brake circuit at the trailer connector. You will need wire to connect the brake positive wire to the trailer connector; use 10-gauge wire # 10-1-1, sold by the foot.

expert reply by: Adam R