Installing Hydraulic Disc Brakes on a 5th Wheel Trailer
Question:
I have searched the web and your site for a schematic or drawing to physically show layout for fifth wheel trailer. I have already ordered all parts from E-trailer just waiting for delivery. Im doing research for running hydraulic lines for this kit to know success even on HydraStar web. can you advise. Also tried to find out what sizes of line from where 1/4inch down to 3/16inch at disc is this correct? need advise as this is new territory for me.
asked by: Roy I
Expert Reply:
I can help you correctly run hydraulic lines on your trailer.
Adding disc brakes is a great idea, but the reason you are having such difficulty finding a schematic is because hydraulic brakes are rarely installed on 5th wheel trailers and they are typically installation specific.
I have made a diagram of a typical setup on a trailer for you to look at. In this diagram I have run the main line down the driver's side frame of the trailer so the shorter lines are needed to the driver's side calipers than the passenger side. You can mount your main line to which ever side is convenient for your trailer.
In the image I have pointed out where the step down from 1/4 inch to 3/16 inch line will be. Also, it is important to note that a rubber line should be run in between the steel line and the caliper, the Hydrastar kit # HS496-252 will include this.
You will want to mount the electric over hydraulic actuator somewhere on the frame of your trailer that is protected by weather conditions but also has an appropriate amount of space to ventilate properly, such as your front storage compartment.
If you continue to have questions, I'd be more than happy to continue to troubleshoot this matter with you.

Product Page this Question was Asked From
Hydrastar Hydraulic Brake Line Kit - Tandem Axle - 25' Long, 3/16" Main Line
- Accessories and Parts
- Brake Actuator
- Trailer Brakes
- Disc Brakes
- Hydraulic Drum Brakes
- 25 Feet Long
- Brake Lines
- Steel Line and Flexible Hose
- Brake Line Kits
- Tandem Axle
- Hydrastar
more information >
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