If your trailer’s old drums are dragging or just not cutting it anymore, this Hydrastar Disc Brake Kit brings a serious upgrade. The electric-over-hydraulic actuator delivers smooth, even braking response through your existing in-cab brake controller, while the 10" Dacromet-coated hub-rotor assemblies give consistent stopping at highway speeds. You’ll feel the difference right away—shorter stops, smoother control, and dependable performance every time you hit the brakes.
Each side comes preloaded with inner (L68149) and outer (L44649) bearings, races, seals, and grease caps already in place. That means no messy packing or extra parts chasing—just bolt them on and connect the lines. Calipers, mounting brackets, and all hardware are included so you can finish the job quickly and get back on the road with minimal setup.
The included actuator installs on the trailer frame and ties into the wiring and brake lines for precise hydraulic pressure that pairs with most in-cab brake controllers (sold separately). The result is fast response time and even braking across both wheels, especially noticeable during sudden stops or downhill runs.
Exposure to rain or road grime won’t slow these brakes down. The Dacromet coating adds rust resistance that helps protect rotors, calipers, and brackets from corrosion over time. That means clean operation season after season—even when you’re towing through wet conditions.
The package comes ready for a single 3,500-lb axle setup with a 5 on 4-1/2" bolt pattern and 1/2" wheel studs. It includes a full hydraulic line kit: one 188" long brake line, one 70" line, two 21" rubber flex lines, plus brass fittings, nylon hose clamps, and self-tapping screws. With all parts in one box and clear specifications—inner race L68111, outer race L44610, grease seal inner diameter 1.719", outer diameter 2.565"—you get a complete system designed for solid braking performance out of the gate.
Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.
Hi, everyone. Steve here with etrailer. Let's take a look at our Hydrastar disc brake kit with included actuator for a single axle trailer. Folks, this is gonna give you 10-inch rotors. The lug pattern is a five on 4 1/2 inch lug pattern, so make sure you're double-checking your lug pattern, or reach out to us if you need assistance on how to figure that out. Now, this is rated for 3,500 pound axles.
And they do include the inner and outer bearings. The seals, the races are already pressed inside of the units themselves, so you don't have to worry about that part. And of course you get your calipers, all your bolts needed for installing the calipers, brake lines, your flexible brake hoses, and of course, your short and long brake lines as well. So they're gonna give you enough brake line to go from the actuator all the way back to the axle beam, and then cross left and right to reach both assemblies for braking. Now, this is the actuator here.
It's an electric over hydraulic actuator. It's pretty beefy. And of course, they got the caps on here just for shipping to keep those threads nice and safe. And on the top here, you can see it does have a nice red one label. It says use .3 or four brake fluid from a new sealed container.
So make sure you're following all the instructions. Again, you have all the wiring. There's a bag full of clips and little screws and bolts here. I left them in there just so I didn't lose them, but you get all of that as well. So let's talk about the assembly here.
So the rotor assembly hub, rotor assembly all in one piece here. It does have a nice decrement coating, so that's why it kinda has that shine, if you will, but that's gonna give you superior protection against rust, corrosion, those kinda things, so these are gonna be great for you for longevity. And with this kit, it's gonna improve your braking capability, your stopping power, so you're gonna have shorter stopping distances versus, like, your electric drum brakes that you probably are used to if you've never used disc brakes. And these are gonna be super effective at highway speeds, heavier loads. These are just by far, a much, much more reliable, better, smoother braking than your traditional electric brakes that you're probably used to. Now, if you've used these before and you're getting this kit 'cause you know just how great they are, great. As I said, you get everything here included with the kit. And like always, if you have questions about this or any other product we carry here at etrailer, reach out to us. We're here to answer any questions we can. And that being said, if we miss something here that you wanna see in the future videos, let us know. We're here to help you. We wanna make sure we give you the best possible information the first time as we possibly can. I'm Steven with etrailer. Thanks so much for your time, I hope this information has been helpful for you, and have a great day.
Ratings & Reviews
The folks at E-trailer are amazing. Great customer service and support. The hydastar ki obviously speaks for itself, superior product by far. Best brake upgrade for marine application on the market.
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