What Is The Difference Between Hydrastar Kits HYD22FR And HYD42FR?
Updated 09/08/2025 | Published 06/03/2025
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Question:
Whats the difference between this kit and the 22FR kit?, is this a complete everything needed to swap from hydraulic surge brakes?
asked by: James
Expert Reply:
Hello James, thanks for reaching out. Both the kits you mentioned, the Hydrastar # HYD22FR and # HYD42FR are complete conversion kits for standard 3,500 lb axles. The difference is the calipers included with each kit.
The # HYD22FR has stainless steel calipers, while the # HYD42FR comes with Dacromet coated calipers. Aside from that both kits come with everything you need to convert to EOH disc brakes. You will just need to make sure your tow vehicle is equipped with a brake controller that is compatible with electric over hydraulic brakes. The Tekonsha P3 # 90195 is what I recommend for that.
What kind of trailer are you wanting to install this on?
Product Page this Question was Asked From
Hydrastar Disc Brake Kit w/ Actuator for Tandem Axle Trailers - 10" Rotor - 5 on 4-1/2 - 3.5K
- Trailer Brakes
- Disc Brakes
- Standard Grade
- 5 on 4-1/2 Inch
- Hub and Rotor
- 1/2 Inch Studs
- 3500 lbs Axle
- 14 Inch Wheel
- 15 Inch Wheel
- Hydrastar
more information >
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Jesse M.
9/8/2025
Hey James, did you decide which brake kit to go with for your trailer? I'd love to know how it worked out for you, as it could help others make a choice between the two kits.