WARNING:
Do not adjust a weight-distributing hitch to any
position where the rear bumper of the vehicle is higher than it
was before attaching the trailer. Doing so will defeat the function of
the weight-distributing hitch, which may cause unpredictable handling,
and could result in serious personal injury.
Weight-distributing hitch – vehicles with air suspension
When hooking-up a trailer using a weight-distributing hitch, always use
the following procedure:
1. Turn off easy entry / kneel feature if equipped.
2. Park the vehicle, without trailer and with the ignition on, on a level
surface with all doors closed for a few minutes to ensure that the air
suspension has settled.
3. Measure the height of the top of the front wheel opening on the
fender, this is H1.
4. Attach the trailer to the vehicle; do not install the weight distributing
bars at this time.
5. With the ignition on and all doors closed, let the vehicle with trailer sit
for a few minutes to let the air suspension re-settle.
6. With the trailer connected, but without weight distributing bars
connected, measure the height of the top of the front wheel opening on
the fender a second time, this is H2.
7. Install and adjust the tension in the weight distributing bars so that the
height of the front fender is approximately halfway between H1 and H2.
8. With the ignition on and all doors closed, let the vehicle, now with
trailer and weight distributing bars connected, sit for a few minutes to
let the air suspension re-settle.
9. Re-measure the height of the top of the front wheel opening,
repeating steps 7-9 as necessary to obtain a fender height approximately
halfway between H1 and H2 after the air suspension has settled.
10. Check that the trailer is level. If not level, remove the trailer, adjust
the ball height accordingly, and repeat steps 4 - 10.
WARNING:
Do not adjust a weight-distributing hitch to any
position where the rear bumper of the vehicle is higher than it
was before attaching the trailer. Doing so will defeat the function of
the weight-distributing hitch, which may cause unpredictable handling,
and could result in serious personal injury.
Tires, Wheels and Loading
219
2012 Navigator
(nav)
Owners Guide, 1st Printing
USA
(fus)
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