Items Needed to Rebuild Boat Trailer Hydraulic Drum Braking System

Updated 12/10/2014 | Published 12/09/2014

Products Featured in This Question

Dexter Zinc-Plated Brake Actuator w/ Drop - Drum - 2-5/16" Ball - Bolt On - 20,000 lbs

(42)

$819.58

Brake Mounting Flange for 3" Round Axle

(35)

$46.55

Trailer Hub and Drum Assembly - 5,200-lb and 6,000-lb Axles - 12" - 6 on 5-1/2 - Pre-Greased

(1373)

$149.70

Question:

Im helping a friend rebuild the brakes on his Load Rite trailer. It is a three axle boat trailer with absolutely no tags on it to identify anything. It is a six lug axle with a 5 bolt flange for the brakes on a torsion axle that is square with a dip at the center. Only the front two axles are currently set up for braking, the 3rd just freewheels. We are pricing out what it will cost to replace everything being that the previous owner didnt maintain it. The hydraulic actuator hasnt moved in what looks like years and the lines/drums are very rusty and corroded. It also has 225/75r15 tires if that helps, just looking for a general direction and maybe some suggestions on products if possible. thanks

asked by: Michael S

Expert Reply:

It sounds like you have a great winter-season project on your hands!

Based on your description of the condition of the existing trailer hydraulic drum braking system it sounds like you'll be replacing just about everything. When in doubt, swap it out.

A good starting point for your project is the linked article on hydraulic drum brakes. This article covers the process of installing drum brakes from scratch but it will still give you all of the considerations to keep in mind when re-building your friend's trailer brake system.

You will need to determine the axles' capacity rating in order to select brake assemblies that are suitably rated and that have the same 5-bolt mounting pattern. The axles may still have stickers on them to indicate their rating but if not the linked article includes a table that will give you examples of typical component combinations for a given axle size and rating. There are hyperlinks within the table that will let you see each of the referenced components.

There is a good chance that the trailer uses 3-inch axles since this size commonly uses 5-bolt flanges # 4-44-1 and a hub with the 6-on-5-1/2-inch wheel bolt pattern like on hub/drum assembly # AKHD-655-6-K. If you have brakes on all three axles you will need to use multiple brake line kits, a tandem kit along with a single-axle kit, in order to have enough lines for all three axles.

expert reply by: Adam R