How is Trailer Braking Affected When Adding Second Brake Axle to Trailer

Updated 09/16/2020 | Published 09/15/2020

Question:

I bought a new aluminum boat trailer with surge brakes. It is a tandem axle. One axle has the Kodiac disk brakes with a titan actuator. The other axle has the mounting plate for brakes. We live in a mountainous area and need all of the braking we can get. I added a dexter 3500 lb axle with electric brakes to a bass boat in the late 80s and it worked very well! In fact the system still works today even though I know longer own the boat. 10 years ago I bought a boat with an aluminum trailer with a similar set up as my new trailer. The disk brakes no longer worked. I also wanted easy lube hubs. I ordered two custom dexter 3500 lb axles with electric brakes from your company and installed them on this trailer. I added a break away battery to the winch stand above the waterline. The whole system is wired to a junction box and uses a 7 wire Bargman plug. My tow vehicle is an F-350 dually with a large slide in camper on it. We tow with a torklift super truss hitch. Its a finely tuned rig that will stop on a dime. Here is the question. How will it work if I add electric brakes to the non-braking axle. It seems that the surge brakes would apply less braking when the electric is applied heavily. The break away will continue to operate as normal. In a panic stop momentum should activate the hydraulic brakes as needed. What do you think? Thanks

asked by: Charles S

Helpful Expert Reply:

Adding a brake axle to a surge brake trailer will increase the stopping power noticeably but will not make the brakes too touch feeling if that makes sense. The pressure created in the actuator and master cylinder would be the exact same so it would be basically two brake axles applying same pressure. Since the surge brakes release when the pressure is released essentially the trailer's new braking power would hold the master cylinder back a bit more so you wouldn't just get double the braking power slammed on under same circumstance.

I would not recommend attempting to have both surge and electric brakes on different axles of the same trailer as that would be nearly impossible to regulate the same braking pressure between the two.

I attached a couple help articles on adding brakes to a trailer axle for you to check out as well.

expert reply by: Jameson C