The Bulldog-style Slide-Lok coupler clamps tight around your 2" hitch ball and stays that way. The sliding collar keeps the jaws fully closed, so you don’t have to worry about the trailer jumping free when you’re pulling heavy loads. A safety pin locks everything in place, giving you a secure connection that holds up run after run. With its 7,000-lb gross towing weight and 700-lb tongue weight rating, it’s built to handle serious work.
Inside the actuator, a tough acetal copolymer liner keeps things moving smoothly. It’s self-lubricating and wear-resistant, so the inner slide glides without sticking or binding. That means your brakes respond consistently when slowing down and stay quiet on the road. The steel housing adds strength, while the hard plastic liner takes care of long-term durability.
This actuator comes already primed, so you can paint it to match your trailer or weld it straight on without extra prep. It fits a standard 3" wide tongue and can be bolted on with 1/2" x 4-1/2" Grade-5 bolts or welded in place if you prefer a permanent mount. You get flexibility to build or upgrade the way you want it.
The glass-reinforced nylon master cylinder won’t rust or pit like metal versions can. Its large reservoir holds more brake fluid, helping prevent air from entering the system and reducing maintenance between trips. An automotive-style diaphragm cap seals out dirt and moisture, keeping your hydraulic drum brakes working smoothly every time you slow down.
A breakaway cable with snap hook is included so your trailer brakes engage automatically if it ever separates from your tow vehicle. It’s a simple addition that adds peace of mind whenever you’re hauling heavy gear or backing into tight spots.
Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.
Hi there, I'm Michael with etrailer.com. Today we're gonna take a quick look at this Demco hydraulic brake actuator. This is a model DA91 surge type hydraulic actuator that's going to activate your trailer's hydraulic drum brakes when your tow vehicle slows or stops. The momentum of the trailer is going to activate to ensure that your hydraulic lines are putting pressure to your drum brakes to make sure that they're applying. This will be a bolt on or a weld on installation. Will install onto a straight three-inch wide trailer tongue.
If you are bolting it on you will require a 1/2 inch by 4-1/2 inch grade five bolts, which are not included as you will have to provide those yourself. But this is constructed here in the USA or it's made here in the USA with a heavy duty steel construction. It's gonna provide a gross towing weight capacity of 7,000 pounds and a maximum tongue weight of 700 pounds. Our bulldog collar lock coupler here is going to fit tightly over a two inch hitch ball for a nice secure connection. We've got the heavy duty design that's going to create a nice fit for your utility, livestock, cargo and construction type trailers.
We have the pin style fastener here that's gonna hold the collar in place around the hinged ball socket there. So when we get connected we can just simply push that forward or when we want to disconnect, we can pull that back. Give you a different perspective on that. So you push in there, just secure it in place and then you can pass your pin through to make sure that it's not going to come disconnected. This does have a composite master cylinder that's gonna be very durable and efficient.
It's constructed of a glass reinforced nylon so it's gonna resist rust and corrosion. You also have a large reservoir that's gonna provide increased capacity for your brake fluid and then an automotive style diaphragm cap here that creates a completely enclosed system to help prevent any contamination of your fluid. We also have acetol copolymer linings that are going to provide a nice smooth operation as the actuator telescopes in and out. This does have a nice primed finish, as you can see. So it is gonna be ready to be painted the color of your choosing.
And of course we do have our breakaway here. This does have the snap hook on the safety cable. That's gonna ensure a nice secure connection to your breakaway. The lever here, if you were to become disconnected at the coupler, this is gonna stay connected and it's gonna pull that lever. Make sure that your trailer's brakes activate so you don't have to deal with a trailer that's propelling itself down the road, bringing it to a nice safe stop. Now because this actuator does not include a reverse lockout, it is recommended that you equip your trailer with free backing brakes so you can drive in reverse without the actuator triggering your trailer brakes because that would essentially cause the unit to telescope in which would apply your brakes. So free backing brakes are a great way to go. So that completes our look for today. Again, I'm Michael with etrailer.com. Thanks for watching.
Customer Satisfaction Score:
74% were satisfied with this product
26% of customers were not satisfied
Ratings & Reviews
My trailer coupler came with instructions. The hydraulic brake actuator coupler came with no instructions. Wish it were the other way around.
I ordered a brake actuator for a trailer that we use at my work. The original actuator showed to be available when I purchased it, but actually had been discontinued. A lady, whose name I will not mention, was very helpful and knowledgeable when explaining the situation to me. She offered a replacement to the original one, and even helped me with the cost. The alternatives were a little more expensive. Thank you Diana H. for your expertise and kindness!
Great product love it
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