If you’re tired of weak or inconsistent braking, this Hydrastar kit transforms how your trailer stops. The electric-over-hydraulic actuator ties into your existing in-cab brake controller and applies the disc brakes with smooth, even pressure. You get consistent stopping even at highway speeds and noticeably shorter stopping distances than drum brakes. It’s a complete system for one axle that includes all lines, fittings, and hardware for an easy upgrade.
Rust and corrosion can quickly ruin conventional brakes, especially when stored outside or exposed to moisture. Each of the two hub-rotor assemblies in this kit comes Dacromet-coated for protection, and the calipers are stainless steel for true rust resistance. These tough materials keep the braking surfaces clean and smooth so you can count on reliable performance season after season.
Everything needed for a single 3,500-lb axle is in the box—no parts hunting required. The kit includes hub-rotor assemblies with inner bearing L68149, outer bearing L44649, races (L68111 and L44610), grease seals with 1.719" inner diameter and 2.565" outer diameter, plus mounting brackets and self-tapping screws. Pre-cut hydraulic brake lines are included: one 188" line, one 70" line, two 21" male/male flex lines, a brass T-fitting, brass union fitting, nylon hose clamps, and everything needed to connect the system.
Disc brakes have only one moving part per caliper—no shoes or springs to adjust or replace—so maintenance is simpler and reliability is higher. Once installed, you’ll notice smoother braking control thanks to even pad pressure across both sides of the rotor. It’s an easy way to bring modern brake performance and peace of mind to your trailer setup.
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 Hydrastar disc brake kit with the electric over hydraulic brake actuator for single 3,500 pound trailer axles, has a five on 4 1/2 inch bolt pattern. Now this is an all inclusive kit, has everything you're gonna need to switch your trailer over to disc brakes for improved performance and greater stopping power. This will include everything shown here. It includes two disc brake end kits for one axle. These hub and rotor assemblies right here have the 1/2 inch diameter wheel studs on them, and they also have the bearing races already pre-installed in them.
Comes with the inner and outer bearings, the grease seals, the stainless steel calipers that have the brake pads in there, and the installation bolts. And the caliper mounting brackets, you can see that we have these, the calipers, mounted too. They are designed to attach to, as you can see, a four bolt brake flange. Now the hub and rotors and the caliper mounting brackets all have a Dacromet coating, which is corrosion resistant. And as we mentioned, the calipers themselves are stainless steel.
Now the brake actuator, I wanna zoom in and show you. This is a Hydrastar electric over hydraulic brake actuator. Basically this part will hardwire into your tow vehicle, and it signals your in-cab brake controller when the brakes are applied, triggering the pump and motor on the actuator. This will help create a smooth even braking with fast response time, and it does work with most in-cab brake controllers. Now the brake controllers are sold separately.
Also, if you notice it comes, let me zoom back out here, comes with the brake line kit that has all the solid brake lines, the flexible lines, and all the fittings you need for a single axle trailer. Now we list on the product page of this product all the part numbers of these parts here that are included with the kit. Now more and more people are switching their trailers over to disc brakes and with a good reason because unlike drum brakes, disc brakes will deliver consistent braking even at highway speeds. Disc brakes also offer a substantially shorter stopping distance, and the disc brake calipers have only one moving part, so there are fewer parts to have to maintain, fewer parts to get damaged, and fewer parts to have to repair or replace. Application for this kit, again, is single axle trailers, 3,500 pound axle capacity, bolt pattern five on 4 1/2 inches.
The rotor diameter is 10 inches and the studs, again, are 1/2 inch. But that should do it for a look at the Hydrastar disc brake kit with the electric over hydraulic brake actuator for single 3,500 pound trailer axles.
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.
Info for this part was:
At etrailer we provide the best information available about the products we sell. We take the quality of our information seriously so that you can get the right part the first time.
Thank you! Your comment has been submitted successfully. You should be able to view your question/comment here within a few days.
Error submitting comment. Please try again momentarily.