Demco Hydraulic Drum Brake Assembly - Single Servo - Galvanized - 10" - Left Hand - 3,500 lbs

Part Number: 18788

51 Reviews | 9 Questions

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demco accessories and parts trailer brakes hydraulic drum

demco accessories and parts hydraulic drum brakes brake assembly 18788

demco accessories and parts hydraulic drum brakes brake assembly

demco accessories and parts trailer brakes brake assembly hydraulic drum - single servo galvanized 10 inch left hand 3 500 lbs

demco accessories and parts trailer brakes brake assembly 18788

demco accessories and parts hydraulic drum brakes 10 x 2-1/4 inch 18788

demco accessories and parts trailer brakes hydraulic drum brake assembly - single servo galvanized 10 inch left hand 3 500 lbs

demco accessories and parts brake assembly 10 x 2-1/4 inch drum 18788

demco accessories and parts trailer brakes 10 x 2-1/4 inch drum hydraulic brake assembly - single servo galvanized left hand 3 500 lbs

demco accessories and parts trailer brakes 10 x 2-1/4 inch drum

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Driver's-side hydraulic trailer brake assembly features a single-plunger design. Galvanized steel resists rust, making the assembly great for boat trailers. Mounting flange has 4-bolt pattern. 1-800-940-8924 to order Demco accessories and parts part number 18788 or order online at etrailer.com. Free expert support on all Demco products. Great prices and Fastest Shipping for Demco Hydraulic Drum Brake Assembly - Single Servo - Galvanized - 10" - Left Hand - 3,500 lbs. Accessories and Parts reviews from real customers.

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Demco Accessories and Parts - 18788

Driver's-side hydraulic trailer brake assembly features a single-plunger design. Galvanized steel resists rust, making the assembly great for boat trailers. Mounting flange has 4-bolt pattern.

Features:

Marine-grade hydraulic drum brake assembly is great for boat trailers
- Designed for use with surge-type trailer brake actuators
Sturdy, corrosion-resistant steel construction
- Galvanized backing plate
- Stainless steel spring hardware
- Zinc-plated wheel cylinder
Single-plunger design delivers 15 - 20 percent braking in reverse
Riveted brake shoes provide increased durability
Periodic manual adjustment required
Mounting bolts sold separately
Made in the USA

Specs:

Configuration: left hand (driver's side)
Dimensions: 10" diameter x 2-1/4" thick
Mounting flange bolt pattern: 4 on 4"
Wheel size: 13" - 15"
Axle rating: up to 3,500 lbs
1-Year warranty

SB18788M Demco Galvanized 10" Marine Trailer Brake Assembly - Single Servo - Left Hand

Customer Satisfaction Score:

95% were satisfied with this product

5% of customers were not satisfied

Wrong item was ordered

5% of customers were not satisfied

Wrong item was ordered

4.8

51 reviews

5 Stars		(44)
4 Stars		(4)
3 Stars		(3)
2 Stars		(0)
1 Star		(0)

by: John 09/08/2018

Afternoon job for both left and right side of 2000 Jayco pop up camper.
Cheaper and easier than break job.

Fast shipping.

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John One Year Later

9/8/2019

It’s been about a year now and 5 or 6 trips up north to camp. Have a boat trailer that I will use this product on yet this fall.

by: Mark 05/13/2018

Put new brakes, drums, bearings and seals and hubs on boat trailer found all parts here and received really fast always order parts for trailers here and always will

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by: Tom 07/31/2015

Great products. Easy cross referencing from old to new replacement. Great info video.

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by: Mathew W. 01/08/2017 One Year Later

When I realized my brakes were in need of repair and no local shop worked on trailer brakes I decided to do it myself.
With the help of the etrailer folks I had a new set of brakes and was ready for another fishing season.
Great products, they do what they say and great customer support.

by: Tom in California 10/25/2016 One Year Later

These worked great. Much easier to replace the whole assembly like this, than replacing all of the original rusted out components. These are galvanized, so they should last a long time. I'm using these for a boat trailer for a 21 foot fiberglass euro styled V8 powered pleasure boat that weighs about 3000 pounds.

by: Robert K. 06/09/2017

So happy i found etrailer. They had the quality parts i had been looking for at a great price. I am equally happy with the speedy free shipping. I recieved the brake assemblies and installed them in less time than it took to locate them. Thank you. You will be my go to trailer parts supplier for all future parts. I have 5 different trailers and am sure i will require your services.
Robert K.

by: Fred B. 09/15/2017

Like the assembly being galvanized to last longer and already assembled. Being labeled for left and right is a nice added touch, but not necessary with single piston cylinders. I added a flush kit to my trailer and had to drill a hole through the plate to add, not a problem.

by: pat splat 05/29/2012

bolted right up. Note: I have a boat, and the only thing missing on the backing plate is the half inch hole for my water flush out that was on my old ones, had to drill one next to the flange mount. I packed a little extra grease in the calipers too.

by: bill 03/31/2016

brakes hubs and bearings arrived very fast.all parts fit perfect.sales person was excellent in helping me with the boat trailer parts.thank you

by: Kurt W. 06/14/2014

Easy to install and fast shipping.

by: Andrew 02/15/2025

Bolted on and works fine. Reason for lowered rating is these are NOT MADE IN USA as stated on the website. I could have bought made in china parts cheaper on the jungle website but I paid more because USA quality matters to me. Need to change description.

Gwendolyn Y.

2/17/2025

Hey Andrew. I do apologize in regard to the miss information that we have. I went out to the warehouse to check these breaks and confirm that we got some incorrect information. I am getting this corrected so that our information is correct going forward. If you need anything, please don't hesitate to reach out to me.

by: Jimm H 07/22/2013

Nice quality product. Easy to install... Well, as easy as any brake job could be. Spend a little bit and buy new bolts when you do this job.

by: Chip 08/04/2016 One Year Later

Perfect fit. Bolt on and go??

by: Gary 05/05/2018 One Year Later

Great products at great prices!

by: jim f 02/09/2017

Very simple to install. Unbolted old and installed new and adjusted. So easy even a caveman could do it.

by: BJ R 04/25/2012

known it didn't come with nuts and bolts. Other than that it was perfect.

by: Lance 06/09/2022

Quick and easy assembly with all the information needed

by: TBird 10/27/2011

have not installed yet but don't anticipate any issuses

by: jack w. 09/26/2012

and will order again!

by: Robert 02/20/2013

Works well.

by: Alex 03/07/2026

by: Gary 05/20/2023

by: Tuncer 09/02/2022

by: Robin 10/12/2026 One Year Later

The drum plate assembly bolted perfectly up. Total time of taking the old assembly, putting the new assembly on and bleeding the break line was a half hour.

by: Mark 05/13/2018

Put new brakes,drums, bearings and seals and hubs on boat trailer found all parts here and received really fast always order parts for trailers here and always will

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See what our Experts say about this Demco Accessories and Parts

Do you have a question about this Accessories and Part?

Recommendation for Installation of a Brake Mounting Flange on a Trailer Spindle and Axle
Welding a mounting flange, possible item # 4-35, is a very precise installation. The flanges need to be installed square and concentric to the hub and drum assembly and each other. If the flange is installed incorrectly rapid brake lining wear, improper braking, trailer dog legging, bearing failure, rapid tire wear and, worst of all, weakening of the axle can occur. Usually special jigs are used to install the flange. The jig will keep the flange square and concentric to the axle and...
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How To Check if Trailer Surge Brakes Are Working Properly On Tandem Axle Boat Trailer
Checking the brakes can be done in two ways. The easiest way is to raise one side of the trailer and spin the wheels while someone applies the surge brakes at the coupler. The better way would be to remove each of the wheels and brake drums and activate the brakes while making sure the wheel cylinders and brake assemblies are functioning properly. After this the first thing I would do is bleed the brakes using the trailers surge coupler to force the fluid from the brake lines and make...
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Correct Replacement for Atwood 159-80770 Braking Assemblies
Yes, the Demco Hydraulic Drum Brake Assembly part # 18788 for left and part # 18787 for right will work well to replace the Atwood 159-80770 Braking Assemblies. They are both 10" x 2-1/4" with a 5 bolt flange so there will be no compatibility issues.
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I Want to Replace All of the Surge Brake Equipment on a 2002 Performance Boat Trailer
The surge brake equipment of your trailer consists of the brake lines, drum brakes and the brake actuator. To ensure I recommend the correct parts for your trailer I will need a little more information. A brake line kit is pretty universal. For a single axle trailer, I recommend using part # T4829900. This kit comes with all of the lines and fittings you will need to replace everything from the actuator to the brake assemblies. For an actuator, I would need to know what type of actuator...
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Drum and Hub Kit, Wheel, and Brake Assembly Recommendation for a 2009 Starcraft 2106
I did some research and found that all of the hub and drum assemblies that would fit on your spindle would be 10 inches in diameter, and I also found that if you have a 10 drum you have to have at least a 13 inch rim, so you would need to upgrade to bigger wheels and tires also. The Trailer Hub & Drum Assembly, part # AKHD-545-35-EZ-K, that you referenced is the correct hub and drum assembly. For brake assemblies I would recommend a Galvanized 10 inch Marine Brake Assembly, part # 18788,...
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Boat Trailer Brake Assembly Recommendation for a 3500 UFP Axles
Yes, the Demco Hydraulic Drum Brake Assembly # 18787 would be the correct assembly for the right hand side of your trailer and the part # 18788 would be the correct assembly for the left hand side of the trailer. If your current brake assemblies only have a 1-3/4 inch width they are not fully utilizing the 2-1/2 inches of drum width that you measured. The bolt pattern of the flange is also the same as what you have. Check out the picture I attached to see these measurements. These assemblies...
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Will Demco Hydraulic Drum Brake Assembly Fit Trailer Axle with 10 inch Hub/Drums
As long as you match up the bolt pattern of the brake assembly you have to the mounting flange of your trailer they will bolt right up. This is typically very easy since nearly all axles use the same 4 and 5 bolt mounting flanges. If your mounting flange has a 4 bolt pattern the part # 18788 that you referenced would bolt right up.
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Replacing The Hydraulic Brake Assemblies On A 1984 Shorelander Trailer
We do carry brakes assemblies that will replace yours. It sounds like the brakes you have now are made by Atwood. They no longer make these and have not for quite some time. What we have to replace them are the Demco # 18787 and # 18788. Fortunately we are dealing with a standard size here with the 10" x 2-1/4". You will be able to easily swap these out and get back on the road.
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Bolt Pattern Size on Galvanized Marine Brake Assembly 18787
The backing plate bolt pattern is 2-7/8 inches on center both ways (square). If we can help further let us know.
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Info for this part was:

Expert Research:

Robert G

Expert Research:

Jameson C

Installed by:

Jeff D

Updated by:

Laura H

Updated by:

Wilson B

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