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  1. Trailer Brakes
  2. Demco
  3. Hydraulic Drum Brakes
  4. 3500 lbs Axle
  5. 10 x 2-1/4 Inch Drum
  6. 14 Inch Wheel
  7. 14-1/2 Inch Wheel
  8. 15 Inch Wheel
Demco Hydraulic Brake Kit - Duo-Servo - Galvanized - 10" - Left/Right Hand Assemblies - 3.5K

Demco Hydraulic Brake Kit - Duo-Servo - Galvanized - 10" - Left/Right Hand Assemblies - 3.5K

Item # DMSB18794M-93M
Our Price: $181.06
Trailer Brakes
This item qualifies for Free Shipping
Shipping Weight: 19 lbs
In Stock
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Driver's-side and passenger's-side hydraulic brakes feature a dual-plunger design. Galvanized steel resists rust, making the assemblies great for boat trailers. Mounting flanges have a 4-bolt pattern. Fit 14" to 15" wheels. Great Prices for the best trailer brakes from Demco. Demco Hydraulic Brake Kit - Duo-Servo - Galvanized - 10" - Left/Right Hand Assemblies - 3.5K part number DMSB18794M-93M can be ordered online at or call 1-800-940-8924 for expert service.
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  • Reviews (15)
  • Q & A (0)
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  • Why etrailer?

Demco Trailer Brakes - DMSB18794M-93M

  • Hydraulic Drum Brakes
  • 3500 lbs Axle
  • 10 x 2-1/4 Inch Drum
  • 14 Inch Wheel
  • 14-1/2 Inch Wheel
  • 15 Inch Wheel
  • Boat Trailer
  • Snow Trailer
  • Dual Servo
  • Demco

Driver's-side and passenger's-side hydraulic brakes feature a dual-plunger design. Galvanized steel resists rust, making the assemblies great for boat trailers. Mounting flanges have a 4-bolt pattern. Fit 14" to 15" wheels.


  • Marine-grade hydraulic drum brake assemblies are great for boat trailers
    • Designed for use with surge-type trailer brake actuators
  • Sturdy, corrosion-resistant steel construction
    • Galvanized backing plates
    • Stainless steel spring hardware
    • Zinc-plated wheel cylinders
  • Dual-plunger design delivers same amount of braking when driving either forward or in reverse
  • Riveted brake shoes provide increased durability
  • Periodic manual adjustment required
  • Adjuster plugs (included) cover access holes to keep dirt and grime out of the assemblies and off of the shoes
  • Left-hand (driver's-side) brake assembly and right-hand (passenger's-side) brake assembly included
    • Mounting bolts and hardware sold separately
  • Made in the USA


  • Dimensions: 10" diameter x 2-1/4" wide
  • Mounting flange bolt pattern: 4 bolt
  • Wheel size: 14" or 15"
  • Axle rating: up to 3,500 lbs
  • 1-Year warranty

SB18794M Demco Galvanized 10" Marine Trailer Brake Assembly - Duo Servo - Left Hand

SB18793M Demco Galvanized 10" Marine Trailer Brake Assembly - Duo Servo - Right Hand

California residents: click here

Customer Satisfaction Score:

Customer Reviews

Demco Hydraulic Brake Kit - Duo-Servo - Galvanized - 10" - Left/Right Hand Assemblies - 3.5K - DMSB18794M-93M

Average Customer Rating:  4.9 out of 5 stars   (15 Customer Reviews)

Driver's-side and passenger's-side hydraulic brakes feature a dual-plunger design. Galvanized steel resists rust, making the assemblies great for boat trailers. Mounting flanges have a 4-bolt pattern. Fit 14" to 15" wheels.


Great shipping communication showing a map of item location. Also shipping was very fast. One of the brake sets had a shoe retainer missing but I found the parts in the box and reattached the shoe.


I bought a horse and carriage business and needed to find parts and you guys had what we needed and got us up and running again . Tried several places local and nobody carried these and never even tried to help as soon as they found out they were for a carriage. Service was prompt and definitely will use you again and recommend you


let me start by saying to etrailer, you have a keeper in Sheila C. , friendly and very helpful, last but not least was the super fast delivery, received my order way ahead of schedule. Thank you Sheila.
Lonnie S.

working fine, big plus addition to my boat trailer
Lonnie S - 12/20/2018


This brake kit is a worthwhile upgrade from base units. Besides the galvanized coating on the base plate, the stainless steel springs offer extra confidence against failure. The double acting actuator should give better braking action particularly when operated by the rather minimal surge system fluid displacement.


Nice brakes. Just what I needed for my boat trailer.


good quality


Really easy to work with and my order arrived 2 days ahead of its scheduled delivery date










See what our Experts say about this Demco Trailer Brakes

  • Can the Duo-Servo Demco Hydraulic Brake Kit Replace a Uni-Servo Dexter Hydraulic Trailer Brake Kit
    The Duo-Servo Demco Hydraulic Brake Kit # DMSB18794M-93M fits 10" hub and drum assemblies as well as the same mounting hole dimensions as the Uni-Servo Dexter Hydraulic Trailer Brake Kit # 23-312-313. This means that you definitely can replace them with the Duo-Servo kit. The Demco Duo-Servo kit is perfect if you have a boat trailer. The galvanized backing plates, stainless steel spring hardware, zinc-plated wheel cylinders will do a much better job at ressisting rust and corrosion from...
    view full answer...
  • Comparing Free Backing and Duo Servo Hydraulic Brake Assemblies
    Good questions. The difference between free backing brakes like the # AKFBBRK-35-D and regular hydraulic drum brakes like # DMSB18794M-93M (referred to as duo or duel servo) is that the wheel brake cylinder has pistons on both sides of the regular/duo servo brakes instead of just the one side on the single servo free backing assemblies. The amount of braking doesn't change much between them, they just function differently yet under the same amount of hydraulic pressure. The duo servo...
    view full answer...
  • Replacement 10 inch by 2-1/4 inch Brake Assemblies for 2007 21' Reinell Boat Trailer
    We don't have replacement brake shoes that fit your assemblies but we do have replacement brake assembly sets that would work great for what you have. If you wanted a free- backing setup we have the # AKFBBRK-35-D which are also dacromet coated to fight corrosion. If you have a reverse lockout on your coupler and don't need free-backing plates we also have the Demco assemblies part # DMSB18794M-93M which are also galvanized.
    view full answer...
  • How To Determine If Your Trailer Has Free-Backing Brake Assemblies When Replacing a Surge Coupler
    To find out if you have free backing brakes, there are really only two ways I can think of to test. First, if your coupler works, you can push your surge coupler to move your trailer in reverse. If the brakes apply, then you know you do not have free backing brakes. If you can move it easily, then your brakes are free backing. If your coupler is broken and thus the reason you are replacing then you will need to go to the second testing option. You will need to pull one of your hubs...
    view full answer...
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  • Are Drums Included with Demco Hydraulic Brake Kit for 3.5K Axles # DMSB18794M-93M
    No, the brake drums are sold separately from Demco Hydraulic Brake Kit # DMSB18794M-93M. The reason is that not everyone needs to replace both the brake assemblies and the drums. There are also at least 5 different bolt patterns for the hub and drum assemblies for 3500 pound axles. The most common bolt pattern is 5 on 4-1/2 so in that pattern for hydraulic brake drums you could use # T1543900CB042 which is sold in quantities of 1.
    view full answer...
  • Replacement Parts For Surge Drum Brake Actuator
    I will be able to help you with the parts you need based on your axle capacity. Your axles are rated at 3,200 lbs. You will need the following items for your surge brakes. You have a hydraulic brake actuator. If you are using a 2" ball with your boat trailer, you can replace your existing actuator with the Demco Hydraulic Brake Actuator - Drum - Zinc - 2" Ball - 8,000 lbs, part # DM8609101. While it is rated for 8,000 lbs, if your trailer is only rated for 4,000 lbs, you must adhere to...
    view full answer...
  • Replacement Brake Pads and Wheel Cylinder for 10 Inch Hydraulic Brake Assemblies on Boat Trailer
    Recommending replacement components like brake pads and a wheel cylinder for a hydraulic brake assembly without knowing who manufactured it would be very difficult. Are there any part numbers or manufacturer information on them? Without any manufacturer information, your best bet would be to simply replace the entire assembly. This way, you'll have all new parts and you'll know your brake assemblies will be good to go for a few years. For a boat trailer, I'd recommend using galvanized...
    view full answer...
  • Recommended Replacement Drum Brakes for Boat Trailer with 3500-lbs Axles
    I recommend using the Hydraulic Brake Kit - Uni-Servo - Free Backing - Dacromet - 10" - Left/Right Hand - 3,500 lbs # AKFBBRK-35-D, which will work with your current setup and are perfect because the Dacromet plating is designed to withstand exposure to water; so they're ideal for boat trailers. These brakes are free backing, so they'll allow your trailer to backup regardless of whether or not you've got a lockout feature on your actuator, and they'll work with a breakaway kit. If you've...
    view full answer...

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Info for this part was:

Employee Lindsey S
Edited by:
Lindsey S
Employee Michael H
Expert Research:
Michael H
Employee Jameson C
Expert Research:
Jameson C
Employee Wilson B
Updated by:
Wilson B
Employee Alexander C
Written by:
Alexander C

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