Ford Mercury Villager 1997 Owner's Manual page 241

Driving
Trailer Towing Tips
Before starting on a trip, practice turning, stopping and backing
in an area away from heavy traffic. Get to know the "feel" of
the vehicle/trailer combination.
Practice backing up. Back up very slowly, with someone outside
at the rear of your trailer to guide you. Place your hand at
the bottom of the steering wheel and move it in the direction you
want the rear of the trailer to swing. Slight movement of the
steering wheel results in a much larger movement of the rear of
the trailer.
When turning, drive slightly beyond the normal turning point so
the trailer wheels will clear curbs or other obstructions.
Allow more room for stopping with a trailer attached. Trailer
brakes should be applied first, whether manually or automatically
controlled, when approaching a stop.
For an easy-to-operate vehicle/trailer combination, the trailer
tongue load should be approximately 10-15% of the loaded trailer
weight.
Make a thorough check of your equipment before starting out on
the road. After you have traveled about 50 miles (80 km), stop
in a protected area and double-check your hitch and electrical
connections. Also check trailer wheel lug nuts for tightness.
When stopped in traffic for long periods of time in hot weather,
place the gearshift selector lever in Park (P) to increase the
engine idle speed. This aids in engine cooling and air conditioner
efficiency. If the engine overheats, press the air intake selector
button to select the fresh air position to stop the air conditioner
compressor. Increase the engine speed for a short time.
Vehicles with trailers should not be parked on a grade. However,
if you must park on a grade, place wheel chocks under the
trailer's wheels as follows:
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