1. Brake Actuator
  2. Demco
  3. Surge Brake Actuator
  4. Disc Brakes
  5. 2-5/16 Inch Ball Coupler
  6. 12500 lbs GTW
Demco Hydraulic Brake Actuator w Electric Lockout - Disc - Primed - 2-5/16" Ball - 12.5K

Demco Hydraulic Brake Actuator w Electric Lockout - Disc - Primed - 2-5/16" Ball - 12.5K

Item # DM8104002
lowest price pledge
Our Price: $414.34
Brake Actuator
This item qualifies for Free Shipping
Shipping Weight: 51 lbs
In Stock
Brake Actuator DM8104002 - Weld-On - Demco
zoom in icon
slider vertical icon
zoom out icon
Comment field cannot be left empty.
Name field cannot be left empty.

Thank you! Your comment has been submitted successfully. You should be able to view your question/comment here within a few days.

Error submitting comment. Please try again momentarily.

Product Images


Surge actuator features a corrosion-proof composite master cylinder. Primed finish is great for welding. eZ-Latch coupler mechanism makes hookup a snap. Electric lockout activates automatically to keep brakes from actuating when in reverse. Call 800-298-8924 to order Demco brake actuator part number DM8104002 or order online at etrailer.com. Free expert support on all Demco products. Guaranteed Lowest Price and Fastest Shipping for Demco Hydraulic Brake Actuator w Electric Lockout - Disc - Primed - 2-5/16" Ball - 12.5K. Brake Actuator reviews from real customers.
  • All Info
  • Q & A (3)
  • Videos (1)
  • Photos
  • Why etrailer?

Demco Brake Actuator - DM8104002

  • Surge Brake Actuator
  • Disc Brakes
  • 2-5/16 Inch Ball Coupler
  • 12500 lbs GTW
  • Weld-On
  • Demco
  • Electric Lockout
  • Straight Tongue Coupler

Surge actuator features a corrosion-proof composite master cylinder. Primed finish is great for welding. eZ-Latch coupler mechanism makes hookup a snap. Electric lockout activates automatically to keep brakes from actuating when in reverse.


  • Hydraulic actuator activates trailer's brakes when tow vehicle slows or stops
  • Electric reverse lockout lets you back up without actuating trailer brakes
    • Solenoid activates automatically when you shift into reverse
  • eZ-Latch coupler mechanism for simple, secure hookup and disconnect
    • Lets you hook up when latch is in closed position - just drop coupler over hitch ball and latch will snap into place
  • Composite master cylinder is durable, efficient, and corrosion-proof
  • Acetal copolymer lining provides smooth operation as actuator telescopes in and out
  • Breakaway included
    • Snap hook on safety cable ensures secure connection to breakaway lever
  • Durable steel construction with sturdy, reinforced outer casing
  • Primed finish
  • Weld-on installation
  • Made in the USA


  • Application: trailers with hydraulic disc brakes
  • Ball size: 2-5/16"
  • Gross towing weight: 12,500 lbs
  • Maximum tongue weight: 1,250 lbs
  • Mounting: straight, 3" wide trailer tongue
  • Model number: DA10
  • 1-Year warranty

When you apply the brakes in your tow vehicle, deceleration occurs and momentum pushes your trailer toward the rear of your vehicle. With surge brake systems, the hydraulic actuator is triggered as your trailer moves forward, once your tow vehicle starts to slow down. When this happens, the actuator contracts, applying force to its master cylinder. This in turn supplies the necessary hydraulic pressure to engage your trailer's brakes.

Electric Reverse Lockout

The electric reverse lockout on this trailer brake actuator is automatically activated when you shift your tow vehicle into reverse. The solenoid wires into your trailer connector - which connects to your tow vehicle - so that it can detect when you are in reverse. When your vehicle is in reverse, the solenoid ensures that the hydraulic actuator does not activate your trailer's brakes, thus allowing you to back up your rig. To use the lockout feature, you must have a 5-pole flat, 6-way round, or 7-pole trailer connector.

eZ-Latch Coupler

The coupler portion of this trailer brake actuator features a simple-to-use latching mechanism known as the eZ-Latch. With this mechanism, hooking up is as easy as dropping the coupler over your trailer hitch ball. The latch does not need to be tugged or manually activated to allow the ball into the coupler socket, nor does it have to be secured in place. Just make sure that the coupler is properly lined up with the ball when you lower it, and the rest is automatic.

Demco eZ-Latch in Use

8104002 Demco DA10 Hydraulic Trailer Brake Actuator for Disc Brakes - Electric Lock-Out - 2-5/16" Ball Easy-Latch Coupler - Weld On - 12,500 lbs

Installation Details DM8104002 Installation instructions

Video of Demco Hydraulic Brake Actuator w Electric Lockout - Disc - Primed - 2-5/16" Ball - 12.5K

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

Video Transcript for Demco Brake Actuator - Surge Brake Actuator - DM8104002 Review

Speaker 1: Today we're taking a look at a Demco Hydraulic Brake Actuator with the Electric Lockout. Now this hydraulic actuator is designed to activate your trailer's brakes when the tow vehicle slows or stops. When you're pulling a trailer, and your vehicle is slowing or stopping, the momentum actually pushes your trailer towards the rear of the vehicle. This unit would be the middle piece, so it'll activate those trailer brakes, when the tow vehicle slows or stops. That's gonna put a lot less strain on the rear of your vehicle. It's gonna protect the braking, the suspension, all of that stuff.This is a really nice design.

It does feature an electric reverse lockout that lets you back up without actuating your trailer brakes. It features a solenoid that activates automatically when you shift into reverse. Your wiring is all located here at the rear, as well as the connection point for the hydraulic brake line. Here at the front of the unit, it features an easy-latch coupler mechanism for simple hook up and disconnect. This unit lets you hook up when the latch is in the closed position.

All you have to do is drop the coupler over the hitch ball, and the coupler will automatically snap into place.This is a trigger latch design, so it has that trigger underneath in order to open and close the actual lever. If you want to add some security, whether you're connected or your trailer's left unattended, you can do so. There's two locations: one right here at the latch, and then one right here right above the ball mechanism, so installing a coupler pin and clip or a couple lock would add security to this unit. Those items are not included. They are sold separately and available at etrailer.com.Now internally, the unit features a composite master cylinder.

It's very durable. It's very efficient and corrosion proof. On top, right here, we have a lever, and then we have a sticker that says, "Brakes on. Do not tow," and "Brakes off. Towable." This is your break-away system, so break away is included.

It has a cable that's connected to that lever, and on the end of the cable is your safety latch snap hook. This attaches to your tow vehicle. In the event where the trailer disconnects from the tow vehicle, the tow vehicle will pull the cable, which will then pull the lever, which will then engage your trailer's brakes, bringing it to an eventual stop.This unit is made from a durable steel construction. It features a sturdy, reinforced outer casing, and it features a nice, primed finish so it's ready for paint. That way you can match your trailer. It is a weld-on installation. Flip it over here. When you are mounting, it is designed for straight, 3"-wide trailer tongues. The product's made in the USA. It's designed for trailers with hydraulic disc brakes. It's designed to work with a hitch ball that's a 2-5/16" ball.The gross towing weight capacity is 12,500 pounds for this unit, and the maximum tongue weight is 1,250 pounds. Located here on top is the easy-to-access cap, which gives you access to the fluid reservoir. Overall, it's a really nice design. It's very sturdy, heavy duty. It's got the shield back here, which protects the connection points, like your wiring and hydraulic brake line connection. That's going to do it for today's look at the Demco Hydraulic Brake Actuator with the Electric Lockout.


Ask the Experts about this Demco Brake Actuator

Do you have a question about this Brake Actuator?

  • Why etrailer.com?

    At etrailer.com we guarantee:
  • Highest quality brake actuator for the best price.

    Our Lowest Price Pledge ensures you will never overpay for the parts you need.
  • Real product know-how.

    We make sure that the products we sell are what we say they are, and that they work the way they are supposed to work. Get real advice from a real person who has the knowledge and expertise needed to solve your problem.
  • Most detailed, accurate brake actuator information available.

    Because we take providing accurate product information seriously, we take our own detailed product photos, demo videos and installation videos, as well as verify measurements, instructions, and vehicle fit information.
  • Installations, made easy.

    We love helping people and have the most highly-trained customer service, hands-on experience, step by step videos and installation instructions.
  • Fast shipping.

    Your order is automatically routed to get out of our warehouse and to your door as quickly as possible. Receive free shipping on orders over $99.
  • Personalized service for life.

    We provide one-on-one, personalized service from the ordering process through the life of your product.
  • Trusted since 1946.

    We've been serving customers since our parts store first opened in 1946 and continue to be recognized by our customers, our vendors and third parties for exceptional service.
  • Returns Policy

    Need to return an item? No problem. Please read our Returns Policy for more information.

Info for this part was:

Written by:
Lindsey S
Expert Research:
Jameson C
Updated by:
Laura H
Updated by:
Hannah L
Installed by:
Cole B

At etrailer.com we provide the best information available about the products we sell. We take the quality of our information seriously so that you can get the right part the first time. Let us know if anything is missing or if you have any questions.