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Demco Hydraulic Drum Brake Assembly - Free Backing - Galvanized - 12" - Left Hand - 7,000 lbs

Demco Hydraulic Drum Brake Assembly - Free Backing - Galvanized - 12" - Left Hand - 7,000 lbs

Item # 42029
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Demco Trailer Brakes - 42029
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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 5-bolt pattern. Call 800-298-1624 to order Demco accessories and parts part number 42029 or order online at etrailer.com. Free expert support on all Demco products. Guaranteed Lowest Price and Fastest Shipping for Demco Hydraulic Drum Brake Assembly - Free Backing - Galvanized - 12" - Left Hand - 7,000 lbs. Accessories and Parts reviews from real customers.
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Demco Accessories and Parts - 42029

  • Trailer Brakes
  • Hydraulic Drum Brakes
  • Brake Assembly
  • Demco
  • 12 x 2 Inch Drum
  • LH
  • Free Backing
  • 7000 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 5-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: 12" diameter x 2" thick
  • Mounting flange bolt pattern: 5 on 3-7/8"
  • Wheel size: 14-1/2", 15", and 16"
  • Axle rating: up to 7,000 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.



SB42029M Demco Galvanized 12" Marine Trailer Brake Assembly - Freebacking - Left Hand




California residents: click here


Video of Demco Hydraulic Drum Brake Assembly - Free Backing - Galvanized - 12" - Left Hand - 7,000 lbs

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.




Video Transcript for Review of Demco Trailer Brakes - FreeBacking Brake Assembly - 42029

Jeff: Hello everybody. This is Jeff at etrailer.com. Today we're going to take a look at this Demco 12 inch by 2 inch left-hand driver's side galvanized hydraulic drum brake assembly for up to 7,000 pound axles. Now this is a Marine grade hydraulic drum brake assembly. It's great for boat trailers. It is designed for use with surge type trailer brake actuators.

It is a sturdy corrosion resistant steel construction. If you notice, the galvanized backing plate works really well with Marine applications. Does also use stainless steel spring hardware and the wheel cylinder right up here is a zinc plated wheel cylinder.Now, this brake assembly is a free backing design. When we say that, the way you can tell it is, is if you look at this D-shaped shoe right here, this is the fallaway shoe. This free backing design will let you back up without engaging the trailer brakes, even if the actuator is activated.

Basically, this fall-away shoe right here, it'll only anchor on the drum when your brakes are engaged as the trailer's moving forward. Because the shoe makes only a slight contact with the drum when it's in reverse, just enough friction is generated so that only a minimal amount of braking occurs when you're in reverse. So because of that, when you go in reverse this free backing assembly will allow you to back up with not putting full pressure onto the brakes.Now, this is a manual adjustment brake assembly. You can see the wheel down here that you turn to adjust it. It will require periodic manual adjustment.

Now, when you go to install this, it will require mounting bolts. Those are not included. We do sell those separately, but basically can see it's a five-hole design so it fits onto a five-hole brake mounting flange. Just slide that on and then use your mounting bolts to attach it.Now, the configurations on this, this is a left-hand driver's side assembly. The way you can tell that...

Now on a new assembly, of course it'll have a sticker that'll say L on it so it'll let you know that, but if that sticker wasn't there, the best way to tell is you look at the length of the pad on the shoes. This pad goes from here to here. This pad goes from here all the way down to here. This is a longer pad. This one's the shorter pad. The shorter pad is your primary shoe. Primary shoe will always face the front of the trailer. That's going to tell you that this is the left-hand driver's side assembly.Now this is designed for axles that are rated up to 7,000 pounds. We did mention the size on this is a 12 inch by 2 inch. What that size means is if you measure the diameter from this shoe all the way over to this shoe, that's your 12 inch measurement and then the 2 inch measurement would be the width of the pad that's on the brake shoes. Now this does require a 12 inch brake drum. We mentioned the five-bolt brake mounting flange pattern, and this does accept wheels size up from 14.5 inch up to 16 inch diameter wheels.That should do it for the review on this Demco 12 inch by 2 inch left-hand driver's side galvanized hydraulic drum brake assembly for up to 7,000 pound axles.


Customer Reviews

Demco Hydraulic Drum Brake Assembly - Free Backing - Galvanized - 12" - Left Hand - 7,000 lbs - 42029

Average Customer Rating:  4.8 out of 5 stars   (18 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 5-bolt pattern.

- 42029
by:

I ordered the assemblies on Thursday expecting their delivery on Monday or Tursday but to my great surprise UPS delivered them on Friday. The salesperson I worked with, Karen was knowledgeable and courteous, simply fantastic. The new assemblies fit perfectly as simply as changing a pair of shoes. Thank you eTrailer.



- 42029
by:

One year of service on boat trailer and no problems. Very satisfied with quality and technical help.



- 42029
by:

Product looks great, fit like a glove. Haven't tried with boat on the trailer, but everything worked perfectly with trailer empty. Wont take boat out of water till September, may know more then.



- 42029
by:

Good comunication. Great products at a very reasonable price. Very helpful and pleasant to deal with. Thx Jim



- 42029
by:

Fit great. Nice quality. No issues at a ll.



- 42029
by:

Good experience all around. Product shipped quickly and bolted right up. Problem solved.



- 42029
by:

No problems, the brakes came in on time and were as described.



- 42029
by:

Installed easy. No problems.



- 42028
by:

Review from a similar Demco FreeBack 12 Inch in Accessories and Parts


They are holding up pretty well. Rust on the star adjusters have rendered them useless. The hubs only show a little rust on the exterior, but substantial rust on the interior. I believe I purchased a set of submersible trailer lights from you a few years ago. The lasted about a year and the LED lights started burning out. About half of them are now functioning. I would rate them as poor. Thank you.



- 42028
by:

Review from a similar Demco FreeBack 12 Inch in Accessories and Parts


I replaced the complete brake system on my trailer. I watched the video for install and proper adjustment. I completed my first trip to Florida and back to Maryland trouble free. 2263 miles The brakes adjust easily, and stop well. They are well made and easy to install.



- 42028
by:

Review from a similar Demco FreeBack 12 Inch in Accessories and Parts


Great product, price. Easy to install complete backing plate vs. brakes and new hardware.



- 42028
by:

Review from a similar Demco FreeBack 12 Inch in Accessories and Parts


Quality parts. Fit great! Received shipment on time. I am buying more trailer parts from etrailer right now.



- 42028
by:

Review from a similar Demco FreeBack 12 Inch in Accessories and Parts


Excellent products, super fast delivery, in future I will continue do business with you



- 42028
by:

Review from a similar Demco FreeBack 12 Inch in Accessories and Parts


One year of service on boat trailer and no problems. Very satisfied with quality and technical help.



- 42028
by:

Review from a similar Demco FreeBack 12 Inch in Accessories and Parts


Good comunication. Great products at a very reasonable price. Very helpful and pleasant to deal with. Thx Jim



- 42028
by:

Review from a similar Demco FreeBack 12 Inch in Accessories and Parts


Good product fit perfectly. Trailer stops great again



- 42028
by:

Review from a similar Demco FreeBack 12 Inch in Accessories and Parts


Good experience all around. Product shipped quickly and bolted right up. Problem solved.



- 42028
by:

Review from a similar Demco FreeBack 12 Inch in Accessories and Parts


No problems, the brakes came in on time and were as described.


18
18

Ask the Experts about this Demco Accessories and Parts

  • Demco Hydraulic Brake Line Kit # DM5426 for Use on 1993 Calkins Trailer in a Marine Environment
    I have confirmed with my contacts at Demco, that the Demco Hydraulic Brake Line Kit # DM5426 is coated with a galvanized finish. With the additional galvanized finish, it provides the additional corrosion resistance that you are looking for compared to steel brake lines. This brake line kit is also 3/16 of an inch in diameter, and is designed for use on single axle trailers. This kit includes lines and fittings needed to run brake fluid from your surge brake actuator to the trailer...
    view full answer...
  • Comparing Demco and Titan 12 x 2 Inch Hydraulic Drum Trailer Brakes
    The difference in price, besides being from two different manufacturers, is the materials. Demco assembly # 42028 is galvanized steel. Titan assembly # T4489600 is Galphorite plated steel. So you could say that a galvanized material is superior to a plated one though the Galphorite is certainly a fantastic product. It also has a better warranty. The matching Titan right hand side assembly is # T4489500. Other than that there isn't a reason why you couldn't use either one provided they...
    view full answer...
  • 12 inch Free Backing Hydraulic Brake Assembly
    Brake Assemblies like the Hydraulic Brake Kit - Uni-Servo - Free Backing - 12" - Left/Right Hand Assemblies - 5.5K to 7K item # AKFBBRK-7 will have the description in the title that the brakes are free backing. We also offer the same size free backing brakes in different finishes. Demco Hydraulic Brake Kit - Free Backing - Galvanized - 12" - Left/Right Hand Assemblies - 7K item # 42029-28. Hydraulic Brake Kit - Uni-Servo - Free Backing - Dacromet - 12" - Left/Right Hand - 5.2K to 7K...
    view full answer...
  • Availability of Corrosion Resistant Brake Assemblies for Boat Trailer
    Because electric brake assemblies like the etrailer.com self adjusting brake assembly part # AKEBRK-7L-SA are not typically used for boat trailers, the assemblies are not specially coated for saltwater corrosion resistance. Boat trailers usually use hydraulic brakes, and would use a hydraulic brake assembly like part # 42029 and # 42028. These assemblies are galvanized for corrosion resistance. To convert to hydraulic brakes, you would need a hydraulic coupler/actuator like part # 099-175-00....
    view full answer...

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Info for this part was:

Employee Jeff D
Installed by:
Jeff D
Employee Laura H
Updated by:
Laura H
Employee Wilson B
Updated by:
Wilson B

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