GMC Canyon Owner's Manual page 308

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.
Driving with a Trailer
Towing a trailer requires a certain amount of
experience. Before setting out for the open road,
you'll want to get to know your rig. Acquaint
yourself with the feel of handling and braking with
the added weight of the trailer. And always
keep in mind that the vehicle you are driving is
now a good deal longer and not nearly as
responsive as your vehicle is by itself.
308
Before you start, check all trailer hitch parts and
attachments, safety chains, electrical connector,
lamps, tires and mirror adjustment. If the trailer has
electric brakes, start your vehicle and trailer
moving and then apply the trailer brake controller
by hand to be sure the brakes are working.
This lets you check your electrical connection at
the same time.
During your trip, check occasionally to be sure
that the load is secure, and that the lamps and any
trailer brakes are still working.
Following Distance
Stay at least twice as far behind the vehicle ahead
as you would when driving your vehicle without
a trailer. This can help you avoid situations
that require heavy braking and sudden turns.
Passing
You'll need more passing distance up ahead when
you're towing a trailer. And, because you're a
good deal longer, you'll need to go much farther
beyond the passed vehicle before you can
return to your lane.