Disc Brake Upgrade on a 2012 Tandem Axle Boat Trailer

Published 03/15/2022

Products Featured in This Question

Demco Surge Brake Actuator w Drop and Electric Lockout - Disc - Zinc - 2-5/16" Ball - 12.5K

(142)

$458.21

Replacement Trailer Hub Bearing - 15123

(2189)

$12.25

Replacement Trailer Hub Bearing - 25580

(2189)

$24.14

Hydrastar Hydraulic Brake Line Kit - Tandem Axle - 25' Long, 3/16" Main Line

(42)

$275.64

Kodiak Disc Brake Kit - 12" Rotor - 6 on 5-1/2 - Dacromet and Stainless Steel - 6,000 lbs

(54)

$697.44

Kodiak Trailer Hub for 5,200-lb to 6,000-lb Axles - 6 on 5-1/2 - Stainless Steel

(54)

$260.71

Dexter Zinc-Plated Brake Actuator - Disc - 2-5/16" Ball - Bolt On - 12,500 lbs

(31)

$652.71

Question:

I need help ing the correct brake system for my boat trailer. My 2012 tandem axle trailer built by Magic has never had brakes and i want to install a hydraulic disc brake system. GVWR 9,480# 15 wheels 6 lug x 1/2 x 2-3/4 c.c. 1. Looking for a bolt on 6k disc brake kit. 2. Bolt on actuator over 3x5 tube. 3. Brake line kit for tandem axles. Coupler to first axle 25 2nd axle 27 Thank you,

asked by: Bryan R

Expert Reply:

I would be happy to help you set up a disc brake system for you 2012 Tandem axle boat trailer. Let's start with an actuator you are going to want the Titan Zinc-Plated Brake Actuator - Disc - 2-5/16" Ball item # T4750800. This is a bolt on actuator that fits 3" channels. It has a 12,500 lbs capacity. I have linked a picture so you can see what it will look like when installed.

For your brake lines you are going to want the HydraStar Hydraulic Brake Line Kit - Tandem Axle - 25' item # HS496-252. I have included a diagram that shows what is included in the kit. As you can see in the picture, you will have enough brake line to go 27-1/2 ft back from the master cylinder which should be sufficient to reach the rear brakes on your boat trailer.

For your disc brakes you are going to want the Kodiak Disc Brake Kit - 12" Rotor - 6 on 5-1/2 - Dacromet and Stainless steel - 6,000 lbs item # K2R526DS. This disc brake kit includes two assemblies with rust-resistant, Dacromet-plated rotors and mounting brackets, with stainless calipers. This kit is enough to do one axle. The dacromet coating provides superior corrosion resistance for freshwater or saltwater use. They have a 300- to 400-Hour salt-spray rating.

The disc brakes fit over a standard idler hub and are held in place by the wheel and wheel bolts. If you can tell me what size bearings you currently have on your trailer I will be able to find you the correct idler hubs. The Kodiak Trailer Hub for 5,200-lb to 6,000-lb Axles - 6 on 5-1/2 - Stainless Steel item # KH42655S fit Inner bearing item # 25580 (1.75" inner diameter) and Outer bearing item # 15123 (1.25" inner diameter).