Hitches
Do not use hitches that clamp onto the vehicle bumper. Use a load
carrying hitch. You must distribute the load in your trailer so that
10%–15% of the total weight of the trailer is on the tongue.
The trailer hitch on this vehicle is part of the vehicle rear crash
safety structure. Do not remove the trailer hitch. Failure to
follow this warning could compromise vehicle crash structure and
increase the risk of injury in a rear end collision.
Weight distributing hitch
When hooking up a trailer using a load equalizing hitch, always use the
following procedure:
1. Park the unloaded vehicle on a level surface. With the ignition in the
ON position and all doors closed, allow the vehicle to stand (without
passengers) for several minutes so that it can level.
2. Turn the air suspension (if equipped) control to OFF.
3. Measure the height of a reference point on the front and rear bumpers
at the center of the vehicle.
4. Attach the trailer to the vehicle and adjust the hitch equalizers so that
the front bumper height is within a
1 2” (13 mm) of the reference point.
After proper adjustment, the rear bumper should be no higher than in
Step 3.
5. Turn the air suspension (if equipped) control to ON.
Note:Adjusting a weight distributing hitch so the rear bumper of the
vehicle is higher than it was unloaded will defeat the function of the
weight distributing hitch and may cause unpredictable handling.
Safety chains
Always connect the trailer’s safety chains to the frame or hook retainers
of the vehicle hitch. 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 trailer brakes are
safe if installed properly and adjusted to the manufacturer’s
specifications. The trailer brakes must meet local and Federal
regulations.
2008 Navigator(nav)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
228
The air suspension system can be enabled or disabled through the
message center. Refer toMessage centerin theDriver Controlschapter.
If the system is off, the rear air suspension will not operate and will not
raise (pump) or lower (vent) while the vehicle is not moving. However, if
the system determines that the vehicle is low or high and needs to make
a height adjustment while driving at speeds above 15 mph (24 km/h), the
system will pump or vent as required. Normal vehicle operation does not
require any action by the driver.
On vehicles equipped with air suspension, turn the air
suspension and the ignition switch off prior to jacking, hoisting
or towing your vehicle.
PREPARING TO DRIVE
Utility vehicles have a significantly higher rollover rate than
other types of vehicles.
In a rollover crash, an unbelted person is significantly more likely
to die than a person wearing a seat belt.
Utility vehicles and trucks have larger tires and increased ground
clearance, giving the vehicle a higher center of gravity than a passenger
car.
Vehicles with a higher center of gravity such as utility vehicles
and trucks handle differently than vehicles with a lower center
of gravity. Utility vehicles and trucks arenotdesigned for cornering at
speeds as high as passenger cars any more than low-slung sports cars
are designed to perform satisfactorily under off-road conditions. Avoid
sharp turns, excessive speed or abrupt maneuvers in these vehicles.
Failure to drive cautiously could result in an increased risk of loss of
vehicle control, vehicle rollover, personal injury and death.
Loaded vehicles, with a higher center of gravity, may handle
differently than unloaded vehicles. Do not overload your vehicle
and use extra precautions, such as driving at slower speeds, avoiding
abrupt steering changes and allowing for increased stopping distance,
when driving a heavily loaded vehicle. Over loading or loading the
vehicle improperly can deteriorate handling capability and contribute
to loss of vehicle control and vehicle rollover.
2008 Navigator(nav)
Owners Guide (post-2002-fmt)
USA(fus)
Driving
246
