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  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 Drop and Electric Lockout - Disc - Zinc - 2-5/16" Ball - 12.5K

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

Item # DM8104311
Our Price: $477.48
You Save: $67.82
Brake Actuator
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Shipping Weight: 54 lbs
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Surge actuator has a rustproof aluminum master cylinder and durable zinc plating. eZ-Latch coupler mechanism makes hookup a snap. Electric lockout activates automatically to keep brakes from actuating when in reverse. 1-800-940-8924 to order Demco brake actuator part number DM8104311 or order online at Free expert support on all Demco products. Great prices and Fastest Shipping for Demco Hydraulic Brake Actuator w Drop and Electric Lockout - Disc - Zinc - 2-5/16" Ball - 12.5K. Brake Actuator reviews from real customers.
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  • Reviews (18)
  • Q & A (0)
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  • Why etrailer?

Demco Brake Actuator - DM8104311

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

Surge actuator has a rustproof aluminum master cylinder and durable zinc plating. 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
  • Zinc plating offers corrosion resistance
    • 200-Hour salt spray rating
  • Heavy-duty, aluminum master cylinder is durable, rustproof, and efficient
    • Built for high-pressure applications
    • Allows 50 percent greater displacement than standard master cylinders
  • Acetyl copolymer lining provides smooth operation as actuator telescopes in and out
  • Built-in drop helps you match tow vehicle height
  • Breakaway included
    • Snap hook on safety cable ensures secure connection to breakaway lever
  • Durable steel construction with sturdy, reinforced outer casing
  • Bolt-on installation
    • Requires 1/2" x 4-1/2" Grade-5 bolts (not included) for mounting
  • 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
  • Drop: 4"
  • 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

Sturdy, Corrosion-Resistant Construction

Made of sturdy steel, this hydraulic trailer brake actuator features a durable zinc coating that is designed to limit rust and corrosion. This zinc coat has a 200-hour salt spray rating. Even the master cylinder is made of rustproof aluminum to further ensure durability.

8104311 Demco DA10 Hydraulic Trailer Brake Actuator for Disc Brakes - Electric Lock-Out - 2-5/16" Ball Easy-Latch Drop Coupler - 12,500 lbs

Installation Details DM8104311 Installation instructions

Customer Satisfaction Score:

Customer Reviews

Demco Hydraulic Brake Actuator w Drop and Electric Lockout - Disc - Zinc - 2-5/16" Ball - 12.5K - DM8104311

Average Customer Rating:  4.8 out of 5 stars   (18 Customer Reviews)

Surge actuator has a rustproof aluminum master cylinder and durable zinc plating. eZ-Latch coupler mechanism makes hookup a snap. Electric lockout activates automatically to keep brakes from actuating when in reverse.


Bolted right up exactly like the old one, bled the brakes, hooked up 2 wires save time & $ compared to the original one which was b/o till November. Just haven't found a place to grease it yet


Fast delivery. Great support.
Was going
to re-build old one and it was cheaper to purchase complete new one!


Very fast shipping. Good price and sales help! Thanks

Great !!
John G - 09/30/2022


Prior to ordering, I was concerned about the length of the brake. Length end to end was provided, but I would have liked mounting area length (8 1/4"), and length behind the mounting (~11 1/4"). Communication was great and they kept me informed.


The actuator itself has been operating flawlessly but as previously documented via emails, the backup solenoid failed on the first usage (i.e., wouldn't release the brake fluid pressure when energized). I had to swap out my old solenoid and reuse it so that the actuator was fully functional. It seems that cheaper solenoids are prone to failure and are being installed on new actuators. I disassembled the failed solenoid, connected the solenoid to a 12.5 VDC power source, and found that the electromagnet wasn't strong enough to lift the valve plunger upon energizing when pressurized by brake fluid. I would suggest that the purchasing department return back to the older style, more reliable solenoids. That is why I only gave three stars on this review.


Great product but FYI, it is not a direct replacement for the comparable TITAN actuator.
Your brake line may be a few inches too short as mine was.
Super fast shipping!


Although I had to drill some new holes for mounting I think that this a very good replacement for my old part.


Experience with Etrailer was great. They sent the part that I ordered and it was not damaged which was a plus. The actuator has been working great since then. I hope to get several years of service from this actuator without any issues.
Thank you Etrailer!

Happy Customer: Gus Rodriguez


Easy ordering online, prompt shipping and delivery. No issues at all. We will order from Etrailer again when parts are required.

The brake actuator works as it should. The mounting points matched up perfectly with the old original unit.
Mitchell - 09/28/2020


Perfect replacement.


The break actuator works great and install was easy , after a year on my boat trailer no problems.


Great product , Exactly what was expected and got here quickly !

Will reorder from this company !! Need products quickly so we can run our business and keep customers happy!


Correct item as advertised. Very fast d elivery.


Works great. Easy to install


Ordered for a friend .
Totally satisfied
Quick shipping .




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