Trailer Brakes; Safety Chains - GMC SIERRA DENALI 2002 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:
D
If you'll be pulling a trailer that, when loaded, will
weigh more than 5, 000 lbs. (2 270 kg) be sure to
use a properly mounted, weight
and sway control of the proper size. This equipment
is very important for proper vehicle loading and
good handling when you're driving.

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. Always leave just enough slack so you
can turn with your rig. Never allow safety chains to
drag on the ground.
4-54
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distributing hitch

Trailer Brakes

If your trailer weighs more than 2,000 lbs. (900 kg)
loaded, then it needs its own brakes
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 brake system can tap into the vehicle's
hydraulic brake system only if:
D
The trailer parts can withstand 3,000 psi
(20 650 kPa) of pressure.
D
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, make the brake tap at
the port on the master cylinder that sends the 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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