Ford 2003 Mustang Owner's Manual page 121

Safety chains
Always connect the trailer's safety chains to the
vehicle. To connect the trailer's safety chains, cross
the chains under the trailer tongue and allow slack
for turning corners.
If you use a rental trailer, follow the instructions that
the rental agency gives to you.
Do not attach safety chains to the bumper.
Trailer brakes
Electric brakes and manual, automatic or surge-type
brakes are safe if installed properly and adjusted to
the manufacturer's specifications. The trailer brakes
must meet local and Federal regulations.
Do not connect a trailer's hydraulic brake
system directly to your vehicle's brake
system. Your vehicle may not have enough braking
power and your chances of having a collision
greatly increase.
The braking system of the tow vehicle is rated for
operation at the GVWR not GCWR.
Trailer lamps
Trailer lamps are required on most towed vehicles.
Make sure your trailer lamps conform to local and
Federal regulations. See your dealer or trailer rental
agency for proper instructions and equipment for
hooking up trailer lamps.
Driving while you tow
Do not drive faster than 88 km/h (55 mph) when
towing a trailer. Do not drive faster than 72 km/h
(45 mph) with any weight on the trailer while
towing on a hot day or in hilly country.
Speed control may shut off if you are towing on
long, steep grades.
Driving
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