Old drum brakes can fade or drag when you need them most. This Hydrastar Disc Brake Kit w/ Actuator for Tandem Axle Trailers upgrades your setup with four 12" hub-rotor assemblies rated for 6,000-lb axles and a 6 on 5-1/2" bolt pattern. The electric-over-hydraulic actuator ties into your existing in-cab brake controller to deliver smooth, even braking and faster response at highway speeds. You’ll feel a clear difference in stopping power and control, especially when towing in traffic or on long grades.
Corrosion can ruin brake performance fast, especially when you’re towing through rain or launching near saltwater. Each of the four disc brake end kits is finished in Dacromet for rust resistance, and the calipers themselves are stainless steel for long-term protection. The actuator’s aluminum construction and weathertight seals allow it to be mounted outside without worry—just avoid blasting it with a power washer so the seals stay intact.
Everything you need for a tandem-axle installation comes in the box—mounting brackets, hardware, and a hydraulic line kit with pre-flared fittings. The kit includes 188", 70", and 21" brake lines, brass T and union fittings, clamps, and self-tapping screws. Bearings (25580 inner, 15123 outer), races (25520 inner, 15245 outer), seals (2.25" ID x 3.376" OD), and grease caps are all included inside the hub-rotor assemblies so you can assemble with confidence and save time on setup.
Disc brakes have only one moving part—the caliper—making them simpler to maintain than drum systems with multiple springs and adjusters. This design means fewer parts to service or replace down the road while delivering consistent braking even under heavy use. With dependable performance and components built for longevity, this Hydrastar kit takes the work out of keeping your trailer braking strong season after season.
Customer Satisfaction Score:
93% were satisfied with this product
7% of customers were not satisfied
Ratings & Reviews
Great setup. Really improved the stopping power of my 36' fifth wheel. Just completed a coast to coast trip. The extra stopping power provided additional safety and peace of mind.
It's been working great for the past year. Wish I had the money to put on all of my trailers.
The quality of the product was good. Everything went together and function as intended. Thanks
Installed fairly easily, works great. Stops much faster than the old drum brakes.
Parts were shipped and received quickly, everything mounted up right and all the hardware needed was included.
Thanks for quickly resolving the shipping problem!!
Nice quality, fast shipment, and fairly easy installation. The brake line from the actuator to the first axle is quite long. I will go back with a custom line in the future, for now just coiled it up. William S was extremely helpful with my order.
Overall a great kit. Only wish would be to use rubber lined SS adel clamps instead of the supplied plastic ones
The items seen good quality but the problem is with Hydrastar as a company, calling out customer service, packaging and shipping departments. If it wasn't for great effort from Fred at etrailer I don't thinkl I would try working with this brand again. The packaging was so bad that the rotors ate themselves up. The studs on one rotor scared the other inside the area where the dust cap sits also ruining several studs. The exterior box was in great shape. It was all on Hydrastar. After a week of waiting Fred finally reached someone. I finally received the replacements with the same subpar boxing as before. This time with only minor scratches. Install went well until we opened the actuator box and found a smashed cap. After another two weeks we finished this two month process with success. Don't try this during camping season and not without etrailers help.
Products just arrived yesterday, even though i requested packaging to be better (saw poor review comments on this before hand), it arrived in 2 large boxes that were battered to hell and opened up with contents exposed. Much to my surprise, it appears all parts are present and undamaged, going to install over weekend and will follow up with after install evaluation.
Prices, promptness of shipping and delivery, and customer service is the best I have ever done business with.
Lauren is the best.
Great product...fast shipping
The manual is pretty bad, mostly because of the wiring diagram. FORTUNATELY, the assistance from etrailer and all the install videos are very helpful!
BUT, there is a need for some videos on installing all of this on a Travel Trailer. Mine is big and heavy, hence needing this kit to start with. Wiring the actuator has been a headache and a challenge because of bad diagrams, manuals and the unique layout of a Travel Trailer vs 5th wheel. The brake parts came in good shape and are of good quality. Yes, the brake parts are hefty and need better packaging from the manufacturer. Fortunately, all arrived successfully in the end.
looks great,not done yet.
Do you have a question about this Trailer Brake?
Condition: Badly Dinged
Notes: Item is missing the actuator and the parts are scratched/gouged.
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