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Demco Hydraulic Drum Brake Assembly - Free Backing - Galvanized - 10" - Left Hand - 3,500 lbs

Demco Hydraulic Drum Brake Assembly - Free Backing - Galvanized - 10" - Left Hand - 3,500 lbs

Item # 40716
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40716 - Hydraulic Drum Brakes Demco Accessories and Parts
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Free-backing, driver's-side trailer brake assembly won't engage when you reverse, even if your hydraulic actuator is activated. Galvanized steel resists rust, making the assembly great for boat trailers. Mounting flange has 4-bolt pattern. 1-833-496-1390 to order Demco accessories and parts part number 40716 or order online at etrailer.com. Free expert support on all Demco products. Great prices and Fastest Shipping for Demco Hydraulic Drum Brake Assembly - Free Backing - Galvanized - 10" - Left Hand - 3,500 lbs. Accessories and Parts reviews from real customers.
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  • Reviews (159)
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Demco Accessories and Parts - 40716

  • Trailer Brakes
  • Hydraulic Drum Brakes
  • Brake Assembly
  • 10 x 2-1/4 Inch Drum
  • Demco
  • LH
  • Free Backing
  • 3500 lbs

Free-backing, driver's-side trailer brake assembly won't engage when you reverse, even if your hydraulic actuator is activated. 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
  • Free-backing design lets you back up without engaging the trailer brake, even if the actuator is activated
    • Riveted, fall-away brake shoe only anchors on drum when brakes are engaged as trailer is moving forward
    • 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"
    • Measurement between center of mounting hole to center of mounting hole: 2-3/4"
    • Diagonal measurement bewteen mounting holes: 4"
  • Wheel size: 13" - 15"
  • Axle rating: up to 3,500 lbs
  • 1-Year warranty


Note: Because free-backing brakes are designed to eliminate nearly all friction between the brake shoes and the drum when you are driving in reverse, a trailer breakaway kit will not be effective should your trailer disconnect from your tow vehicle while you are backing up.


Free-backing brakes let your trailer move in reverse without the brakes being activated by your surge actuator. These brakes are needed if your actuator does not have a reverse lockout, which is a mechanism that ensures that the actuator does not activate when your rig moves in reverse.


Demco Free-Backing Brake with Fall-Away Shoe

This Demco free-backing brake assembly has a fall-away shoe that is designed to provide full braking action when your trailer is moving forward and to supply only limited friction when the trailer is moving in reverse. This is largely due to the incorporated dual springs at the shoe's pivot point. (One spring sits on either side of the shoe lever, so only a single spring is visible when looking at the brake assembly.)


Demco Free Backing Brake Labeled Diagram - Left Hand Assembly

When your rig is moving forward and you engage the trailer brakes, the fall-away shoe expands normally, with the leading edge of the shoe catching the drum. This occurs because the plunger on the hydraulic cylinder pushes on the shoe lever, forcing the leading edge of the brake shoe into the drum. Once that edge catches, the dual springs at the shoe's pivot point facilitate braking by forcing the rest of the shoe to pivot into the drum. The action of the shoe against the drum provides the friction required for braking.


When you are driving in reverse, however, the hydraulic cylinder and the springs work against one another. Even though the plunger pushes on the shoe lever, the dual springs of the fall-away shoe overcome the pressure from the brake cylinder, keeping the leading edge from catching on the drum and ensuring that the shoe does not fully pivot into the drum. Because the shoe makes only slight contact with the drum, just enough friction is generated so that only a minimal amount of braking occurs when you are in reverse.



SB40716M Demco Galvanized 10" Marine Trailer Brake Assembly - Freebacking - Left Hand




California residents: click here


Customer Satisfaction Score:


Customer Reviews

Demco Hydraulic Drum Brake Assembly - Free Backing - Galvanized - 10" - Left Hand - 3,500 lbs - 40716

Average Customer Rating:  4.8 out of 5 stars   (159 Customer Reviews)

Free-backing, driver's-side trailer brake assembly won't engage when you reverse, even if your hydraulic actuator is activated. Galvanized steel resists rust, making the assembly great for boat trailers. Mounting flange has 4-bolt pattern.

by:

Assembly arrived quickly and in good shape. A relatively easy installation onto my boat trailer was supported by the useful instructional video. I will continue to use etrailer.com for my trailer parts.




by:

Great company to deal with. Impressive and Professional. Very reasonable in pricing.
Products purchased; trailer Drum and hydraulic surge brakes. Fitted and Work's perfectly. Sad to see everything is made in China.




by:

Product arrived in a timely manner. The visual tracking in route was a plus and very informative. All parts were packed well and in perfect condition. Thanks etrailer for your service and installation videos. My boat is up and running and ready for the water.


Comments
On going issues with the left driver side brake. Keeps locking up after a hard brake. Not sure how to correct this issue. I have installed surge brakes on other boat trailers and this is the first I cannot correct. Please help.
Ron D - 07/05/2016


by:

Excellent services,..Thankful




by:

received, installed, working good.


Comments
After getting the adjustment loose enough the brakes have performed well. I am pleased with the brake system.
Bob F - 05/14/2015


by:

brake assemblies arrived quickly , correct match for my boat trailer. Good price .I will recommend this company to my friends


Comments
No problems. Satisfied customer
Paul B - 01/14/2016


by:

Got these with the Demco hitch to replace an old attwood system. Replaced as old brakes were well packed with bearing grease, not a typo. Hardest part was getting off the old 4 nuts on the bolts holding on the old brake plates. Twenty years and at least three coats of paint made removal almost impossible, thank you aero-kroil,sp?? If I had used them, I'd let you know how those free-backing things fair.




by:

This brake assembly bolted right up and installed in minutes. Much faster and easier (and more cost efficient) than replacing just the failed parts of the original brakes (frozen wheel cylinder and shoes). The "free backing" feature doesnt seem to work all that well. I can feel a heavy amount of drag in reverse and leave tire marks from my trailer all the way up my sloped driveway unless I manually engage the reverse lockout on my actuator. I purposely bought this set so I wouldnt have to do that anymore.




by:

I needed brake shoes and wheel cylinders for my tandem axle trailer; etrailer is the only place that I could find what I was looking for. The Demco hydraulic drum brake assembly had everything I was looking for with steel wheel cylinders and riveted shoes.Great quality and fit. Fast shipping; knowledgeable customer service. Thanks, etrailer.




by:

I ordered a new set of brakes for my boat trailer. They arrived in a timely manner right to my door step. The replacement parts were identical to the originals and were easily installed. The ordering process was easy and the door step delivery very convenient. Also, the parts were cheaper than what I would have paid locally.




by:

These brake parts were easy to install after watching the videos at etrailer.com. I installed brakes on both wheels on my boat trailer along with new seals and they work great. I've only taken a test drive, but the new brakes really help.




by:

Ordered replacement brake assemblies for my aging boat trailer. Catalog and ordering info on the website was very helpful. Parts were in stock, order was filled in a very timely fashion and showed up on my doorstep as predicted by the shipping tracker info. Flawless experience. Thanks, etrailer!




by:

The hydraulic drum brakes with backer plates, I ordered came on time and fit great. I also installed new bearings and they fit good too. I will use them again when I need more parts.




by:

The product was as advertised. It would have been nice if new bolts had been provided. I had gotten another set from another company and they included the 4 new bolts. I should have paid more attention. Not etrailers fault at all. It was as advertised. However, using old bolts to put on new brake drum assembly is not the best.




by:

Hydraulic trailer drum brakes. Received within a few days. Easy to install, not that complicated. Needed a second person to help bleed the brakes.




by:

Fit just fine. Glad to get rid of the rusty originals. Only oddity is that the bleeder screw appears to be metric (10) instead of 3/8" like the originals. They are also a bit loose in their bore so when you back bleed the system (ie pump brake fluid from the bleeder to the brake reservoir, a fare amount of fluid leaks out around the bleeder threads. Not a big deal. just a bit messy.




by:

Perfect replacement for my old rusted boat trailer brakes. Assembly was straight forward. Brakes release well in reverse. All I could ask for.




by:

Product was good . I had a little problem with one of the backing plates not fitting correctly . After determining it was bent., I took everything off the new backing plate and put them on one of the old ones and reused it and everything worked fine




by:

The parts fit correctly to the axle. The bearings & races came out & installed without any malfunctions. It was even easier to adjust the brakes. The master cyl. bled out great & was easy to replace a long with the damper shock. The people I dealt with especially Erika all help tremendously. A terrific experience all along.




by:

This product was reasonably price so I purchased it instead of piece parting it. It made the job much simpler. The only thing we have to do at the one year mark is to check the adjustment I would recommend this product to anyone thinking of rebuilding their trailer brakes.




by:

Extremely fast delivery and very well made. Hard to install than video indicated but not due to the brake product. The old brakes where install with Blue Loctite and required heating with torch to get them off using an impact wrench. After getting the old brakes off, installation was a breeze! High recommend this product.




by:

Great product for boat trailers, made renewing my brakes easy




by:

Excellent experience. Quick shipment. Great price. Good product (trailer drum brake assembly)




by:

these replacments for my boat trailer were and are very good and have held up to my standards for me , nice and easy replacment !




by:

Had them for about a year. Work great. No rust, they stand up to the salt water. Plenty of braking power, but not too much where the trailer feels like it's pulling you back.



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