This actuator starts with a strong steel body that’s built for serious towing. The primed finish gives you a clean surface that’s ready for paint, so you can match it to your trailer and protect it from the elements. Once welded in place, it’s solid and stable — ready for repeated use without flexing or fatigue.
The composite master cylinder is made from glass-reinforced nylon, which resists rust and corrosion much better than steel or aluminum. Its large reservoir gives you extra brake fluid capacity to help prevent the system from running dry, even on long hauls. The automotive-style diaphragm cap seals the system completely, keeping dirt and moisture out so your brakes stay consistent and smooth.
The built-in adjustable channel makes setup simple. With five mounting positions on the 12" channel, you can dial in the height of your coupler so your trailer sits level. The channel-down layout allows for extra drop, which makes it especially useful when lining up taller trailers to a hitch. You can mount a standard ball coupler, lunette ring, or clevis attachment (each sold separately) — whatever fits your build best.
This surge brake actuator automatically applies braking force when your tow vehicle slows down. As the trailer moves forward, the actuator compresses and pushes hydraulic pressure to your drum brakes. That means dependable braking performance without the need for electronic controllers — just smooth engagement every time you stop.
The integrated breakaway system provides peace of mind in case of an accidental uncoupling. If the trailer disconnects, the breakaway engages the brakes automatically to bring things to a quick stop. It’s a simple safeguard built right in, ready whenever you need it.
Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.
Hello everybody. This is Jeff with etrailer.com. Today I'm gonna take a look at this Demco 12-inch, adjustable, channel down hydraulic drum break actuator. Has a 12,500 pound gross tow weight capacity and has a primed finish to it. Now this hydraulic actuator will activate your trailer's brakes when your tow vehicle slows or stops. Basically what happens is when you apply the brakes in your tow vehicle, deceleration occurs, and the momentum will push your trailer toward the rear of your vehicle and with a surge brake system this actuator then triggered as your trailer moves forward, once your tow vehicle starts to slow down.
And when this happens, is this actuator will contract, applying force to the master cylinder in the back here and this in turn will supply the necessary hydraulic pressure to engage your trailer's brakes. This one here uses an acetal copolymer lining to provide a nice smooth operation between this inner portion and the outer case, so the actuator will telescope in and out very easily. We mentioned this as an adjustable channel down. Has five different mounting positions for your coupler. Now the coupler is not included.
We do sell that separately. And the channel down design, you can see most of the channel is down. That allows for greater drop for tall trailers. The channel height, we had mentioned. If we measure from the very bottom to the top, it's gonna be right at 12 inches.
The channel width, which is measured inside to inside, is three inches. This is a heavy duty steel construction, has a nice primed finish to it. Now it does use a composite master cylinder back here, which is durable and efficient. It's a glass-reinforced nylon construction, so to resist rust and corrosion. And it provides a large reservoir to provide increased capacity for the brake fluid.
If you notice up at the top here where you put your brake fluid in, it does use an automotive style diaphragm cap. Creates a completely enclosed system to help prevent contamination of your brake fluid. Right here, this is your breakaway cable and the hook. It's all included. You can see it has a latch on this hook, but this is required by law. And what this does, it'll prevent a trailer, runaway situation. So what you do is when you hook up your trailer to your tow vehicle, you'll also hook up this breakaway cable to your tow vehicle. And when it's hooked up, what'll happen is, if by chance, this comes disconnected from your tow vehicle, it'll pull on this cable, which will activate the lever here which will then supply that pressure again to your master cylinder to apply the trailer brakes. So it does prevent a trailer runaway situation. And as we mentioned, it is required by law. Now this is a weld on installation. It is designed to mount to a straight three-inch wide trailer tongue. This part is made in the USA. Application. This is for trailers with hydraulic drum brakes. Gross towing weight capacity again, is 12,500 pounds, maximum tongue weight of 1,250 pounds. This does go by model number of Da10. And one last thing I do wanna mention about this actuator, because this one does not include a reverse lockout solenoid on the back here, it is recommended that you equip it with either a reverse lockout solenoid that'll screw into your master cylinder back here, or that your trailer would have free-backing brakes, so that you could drive in reverse without this actuator triggering your trailer's brakes. But that should do it for the review on this Demco, 12-inch adjustable, channel down, hydraulic drum brake actuator. With the 12,500 pound gross towing weight capacity.
Ratings & Reviews
Heavy duty steel, quality product. Thank you
Great customer service. Product arrived lightning fast! We would buy again. Thanks!
Thanks you! a great experience with the ordering and receiving my parts that I needed. I would recommend Etrailer.com to anyone needing competitively priced and quality parts fast.
I purchased the 20k lbs surge brake.So far really good. Heavy duty.
Very nice working with you guys. Timely response and delivery. Thank you
Etrailer is the best store for parts.best prices,fast deliver,on time and safe,300 per cent hapy.the etrailer be mi store for ever.
Really happy with customer service and flexibility with shipping to Hawaii.
I think the demco actuator is grate
excellent quality, unbelievable delivery time.
We're replacing old brake units on our fleet of tank trailers. These Demco actuators have a longer adjustment channel than the ones we could get locally, and they were cheaper. Great customer service also!
Package wasn't the greatest, it was a heavy item and should have been packaged a little better, box was torn and one of the clips that holds the pins in place was missing
It does the Job. I tried to talk them in to going with an electric over hydraulic Disc system but the did not want to spend the money with this set up at least is has some brakes.
It worked out very well for us and was very affordable.
Anna did a GREAT job on getting the trailer parts I needed give her a raise :-)
Great quality excellent service
The product delivered was exactly what we ordered. It arrived within only a few days and the package showed up with zero damage. We will continue to order from eTrailer. 5 Stars!!
Quality is great and exactly what I was looking for in a Brake Actuator. Customer service was super friendly and online invoice and tracking was speedy and easy to obtain! Highly recommend.
Worked perfect, exactly as described.
A perfect fit and it took paint beautifully. Upon brake testing, it performed as an OEM! Customer Service was extraordinary.
Welded it together, haven't used it yet.
I am building a very strong utility trailer for a Mustang Skid Steer- I'm a welder by many years- and strong matters. I will put a 'dully' axel under a dump truck body with hydraulic breaks- thus you product was a perfect fit- strong, functional and safe. Thank you for your design intelligence and craftsmanship. I am set up for two trucks- a big one, Mack B-81SX, and a pick-up.
we received in the hitch, we installed it without a problem.
the tech tried to beleed the brakes.
the tech was having problems with the master cylinder sticking.
we ordered in a replacement master cylinder in. after the new master cylinder was installed the tech bled the brakes with no issue. we received the hitch in with a bad master cylinder
Well built just replaced a old unit that been sitting for years and had been jackknifed
received in a timely manner product was just what I ordered nice to have the right parts
Excellent product,service and price. I was notified at every stage where my item was on its journey without contacting etrailer other than placing my order. They have their "stuff " together.
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