Trailer Brakes; Safety Chains - GMC 2003 Sonoma Owner's Manual

Hitches
It's important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough roads are
a few reasons why you'll need the right hitch. Here
are some rules to follow:
•
If you use a step-bumper hitch, your bumper could
be damaged in sharp turns. Make sure you have
ample room when turning to avoid contact between
the trailer and the bumper.
•
If you'll be pulling a trailer that, when loaded, will
weigh more than 3,500 lbs. (1 589 kg) be sure to
use a properly mounted, weight-distributing
hitch and sway control of the proper size. This
equipment is very important for proper vehicle
loading and good handling when you're driving.
•
If your vehicle has the bumper delete option, do not
bolt any type of hitch to the close-out panel. The
close-out panel will not support a hitch.

Safety Chains

You should always attach chains between your vehicle
and your trailer. Cross the safety chains under the
tongue of the trailer to help prevent the tongue from
contacting the road if it becomes separated from
the hitch. Instructions about safety chains may be
provided by the hitch manufacturer or by the trailer
manufacturer. For trailers up to 3,500 lbs. (1 589 kg) you
may attach the safety chains to the attaching points on
the bumper. For heavier trailers, follow the trailer or
hitch manufacturer's recommendation for attaching
safety chains. Always leave just enough slack so you
can turn with your rig. Never allow safety chains to drag
on the ground.

Trailer Brakes

If your trailer weighs more than 1,000 lbs. (450 kg)
loaded, then it needs its own brake–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.
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