The 12" adjustable channel-down design on this Demco actuator makes it easy to line up a tall trailer for a level tow. With 5 mounting positions, you can set your coupler exactly where it needs to be for proper height. The channel-down layout gives more drop than a center-mounted style, which helps if your hitch sits higher. It accepts different coupler types like a ball coupler, lunette ring, or clevis attachment (sold separately), so you can match your specific setup without extra adapters.
This surge actuator automatically applies your trailer’s drum brakes when your tow vehicle slows down. Inside is a composite master cylinder made from glass-reinforced nylon that resists rust and corrosion better than steel or aluminum. It has a large reservoir that keeps more brake fluid on hand, which means fewer refills and steadier braking pressure. The automotive-style diaphragm cap seals the system completely to help keep the fluid clean and the brakes consistent.
The internal acetal copolymer lining keeps the actuator sliding smoothly when it telescopes, even under heavy load. The heavy-duty steel construction gives it durability for repeated use, while the primed finish is ready for paint so you can match it to your trailer frame. It’s built for a weld-on installation on a straight 3" wide tongue, giving you a solid connection rated for 8,000 lbs gross towing weight and 800 lbs maximum tongue weight.
A built-in breakaway system is included to keep your trailer from rolling free in the event of an accidental disconnect. It automatically activates the trailer brakes if separation occurs, helping protect both your load and what’s around it.
If you need to back up without brake drag, this actuator works with the Demco Reverse Lockout Solenoid #DM11993 (sold separately). You can also pair it with Demco’s eZ-Latch couplers or lunette rings to tailor it for your setup in black, zinc, or primed finishes. Everything matches up with the DA91 internal components, so replacements and upgrades stay simple down the road.
Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.
Hello everybody, this is Jeff at etrailer.com. Today, we're gonna take a look at the Demco 12 inch Adjustable Channel Down Hydraulic Drum Brake Actuator, has an 8,000 pound gross towing weight capacity, and is in this nice primed finish. Now, this hydraulic actuator is what'll 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. So with a surge brake system like this, this actuator is then triggered as your trailer moves forward once your tow vehicle starts to slow, and when that happens, the actuator, this inner slide portion will slide back into this outer case, and applies force to the master cylinder in the very back here, and this in turn will supply the necessary hydraulic pressure to engage your trailer's brakes. This one has an acetal copolymer lining right here, provides a nice smooth operation as that inner slide goes into the outer tube as it telescopes in and out.
Up front here, we mentioned has this adjustable channel, has five different mounting positions for your coupler. Now, the coupler is not included, we do sell those separately on our website. This one we mentioned, as you can see, is a channel down design, so it allows for a greater drop, so it works well on tall trailers. Just to give you an idea of the height on that channel, bottom to the top 12 inches tall, the width, which is inside to inside is approximately three inches wide. This is a heavy-duty steel construction, has a nice primed finish to it.
The very back here, we mentioned the master cylinder, it is a composite master cylinder, which is very durable and efficient. It's a glass reinforced nylon construction, which will resist rust and corrosion, has a large reservoir on it, which will provide increased capacity for your brake fluid. And if you noticed at the top here where you put your brake fluid in, it uses the automotive style diaphragm cap, which will create a completely enclosed system to help prevent contamination of your brake fluid. Also, right at the very top here if you noticed, it includes the breakaway cable with the hook included and the keeper on it. Now, this breakaway cable is required by law, and the reason is it prevents a trailer runaway situation.
So when you hook your trailer up to your tow vehicle, you also take this hook and hook this to your tow vehicle. And what that does is in case your trailer gets detached from your tow vehicle, it will pull on this cable, which will activate this lever, which would then supply the pressure to the brake cylinder, the master cylinder back here, and that'll engage the trailer's brakes and prevent a runaway trailer situation. But again, it is included, and as we mentioned, it is required by law. We're gonna hook this back up. Now, this is a weld-on installation, it's designed to mount on a straight three inch wide trailer tongue, it is made in the USA.
Few specs again, this is for trailers with hydraulic drum brakes, gross towing weight capacity is 8,000 pounds, maximum tongue weight capacity is 800 pounds, model number, this actuator goes by the model number of DA91. And one last note I do wanna mention, if you look on the back here where the master cylinder is, because this actuator does not include a reverse lockout solenoid on it, it is recommended that you equip your trailer with either the reverse lockout solenoid or to have free-backing brakes on your trailer, so that you can drive in reverse without the actuator triggering your trailer's brakes. But that should do it for the review on the Demco 12 inch Adjustable Channel Down Hydraulic Drum Brake Actuator with the 8,000 pound gross towing weight capacity.
Ratings & Reviews
Everything arrived in advance of expected delivery date and customer service was excellent.
Heavy duty steel, quality product. Thank you
Great customer service. Product arrived lightning fast! We would buy again. Thanks!
I purchased the 20k lbs surge brake.So far really good. Heavy duty.
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.
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.
excellent quality, unbelievable delivery time.
I think the demco actuator is grate
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.
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
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!
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 :-)
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.
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!!
Great quality excellent service
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.
GREAT AS ALWAYS
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.
Well built just replaced a old unit that been sitting for years and had been jackknifed
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
Really happy with customer service and flexibility with shipping to Hawaii.
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