If your trailer weighs more than 1,500 lbs (680 kg) loaded, then it needs its own brakes — and they must be adequate. Be sure to read and follow the instructions for the trailer brakes so you’ll be able to install, adjust and maintain them properly.

Your trailer’s brake system can tap into the vehicle’s hydraulic brake system only if:

• The trailer parts can withstand 3,000 psi (20 650 kPa) of pressure.
• The trailer’s brake system will use less than 0.02 cubic inch (0.3 cc) of fluid from your vehicle’s master cylinder. Otherwise, both braking systems won’t work well.

You could even lose your brakes.

If everything checks out this far, then make the brake fluid tap at the port on the master cylinder that sends fluid to the rear brakes. But don’t use copper tubing for this. If you do, it will bend and finally break off. Use steel brake tubing.