Disc Brake Conversion Kit for a 5th Wheel Trailer w/ 7,000 lbs Axles

Updated 10/30/2025 | Published 10/05/2025

Products Featured in This Question

Hydrastar Disc Brake Kit w/ Actuator for Tandem Axle Trailers - 13" Hub/Rotor - 8 on 6-1/2 - 7K

(64)

$2162.02

Hydrastar Disc Brake Kit w/ Actuator for Tandem Axle Trailers - 13" Hub/Rotor - 8 on 6-1/2 - 7K

(3)

$2550.02

Question:

Looking for disc break conversion assembly with hydraulics for the following 7K axle: Curt70A-SBSA-86.5-68.5-NOSP-OS-L-C865H-9/16-7279-BRONZE-30PT Serial Number: S010869823

asked by: Bill A

Expert Reply:

Hey Bill thanks for the information. The C865H-9/16 in that axle tag number means you have 8 on 6-1/2 hubs with 9/16" lug studs. The Hydrastar item # HSE7K-T1, you were looking comes with 1/2" lug studs. You'll need the Hydrastar Disc Brake Kit w/ Actuator item # HYD87VR instead.

What brake controller do you have and what tow vehicle are you using?

You can add this information and any other questions you have where it says Reply to Jerred H and I'll be happy to answer them.

expert reply by: Jerred H

Hydrastar Disc Brake Kit
(click to enlarge)

Bill A.

10/6/2025

Hi, Jerred. Thank you for the information. The brake controller is factory-integrated in my 2024 Ram 3500 DRW LWB Tradesman. I welcome your thoughts.

Jerred H.

10/7/2025

@BillA You're welcome! The actuator included with item # HYD87VR is compatible with your factory brake controller. Some of them require an additional adapter item # HBA-CAM. However, you will not have to worry about this. You'll just want to make sure you have yours on the EOH setting.

Bill

10/7/2025

@JerredH Sounds good. Thank you for the information. Can I get a quote for parts only shipped to me (Weatherford, TX 76087) and another quote for parts & labor? I welcome your thoughts and considerations.

Jerred H.

10/7/2025

@Bill You're welcome! Shipping is going to be free on an order that big. You would need to contact a local installer for a quote on labor. If you go to the product page of the Hydrastar item # HYD87VR and scroll down below the pics on the left side you'll see a box that says, SCHEDULE AN INSTALLATION. Go ahead and click on it and it will take you to a page where you'll be able to enter your zip code. Once you do this you'll be connected to our network of reputable installers in your area.

See All (7) Replies to Bill A. ∨

Steve M.

10/30/2025

Jerred I ordered a complete disk brake kit for a 2014 bighorn with 7000 # axels yesterday from etrailer I been watching videos see I may need a extra part for my controller I have a 2024 GMC 2500 HD. Durmax

Jerred H.

10/30/2025

@SteveM Hey Steve. What brake controller do you have in your 2024 GMC 2500? If you have the factory controller you will not need the HydraStar Electric Over Hydraulic Actuator Adapter item # HBA-CAM. The 2024 factory brake controller doesn't have any compatibility issues like we see in older GM ones made before 2017.