Safety Chains; Trailer Brakes - Hummer 2003 H2 Owner's Manual

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.
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Trailer Brakes

If your trailer weighs more than 2,000 lbs. (907 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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