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Integrated hitch rating
The standard integrated hitch has two ratings depending on mode of
operation:
•Weight carrying- requires a draw bar and hitch ball. The draw bar
supports all the vertical tongue load of the trailer.
•Weight distributing- requires an aftermarket weight distributing
system which includes draw bar, hitch ball, spring bars and snap-up
brackets. The vertical tongue load of the trailer is distributed between
the truck and the trailer by this system.
Mode Maximum Gross Trailer
Weight - lb. (kg)Maximum Tongue
Weight - lb. (kg)
Weight
carrying6000 (2721) 600 (272)
Weight
distributing8950 (4059) 895 (405)
These are hitch ratings only; actual vehicle ratings are dependent on
engine, transmission and axle combinations.
Towing trailers beyond the maximum tongue weight exceeds the
limit of the towing system and could result in vehicle structural
damage, loss of vehicle control and personal injury.
Trailer hitch cover
Your vehicle is equipped with a removable trailer hitch trim cover. To
remove the trim cover:
1. Loosen the two
1 4-turn fasteners
in the bottom of the cover by
turning them counterclockwise. Pull
the cover downward to remove it;
the fasteners will remain attached to
the cover.
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Owners Guide (post-2002-fmt)
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Tires, Wheels and Loading
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Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box
Description
32 20A* Fuel pump
33 20A* Back-up lamps
34 25A* Trailer tow connector (stop/turn
lamps)
35 20A* 4x4 module
36 10A* Powertrain Control Module
(PCM) – Keep alive power,
Canister vent
37 15A* Transmission B+
38 30A** Third row seats (passenger side)
39 50A** Air suspension pump
40 30A** Starter motor
41 20A** IP/Console power point
42 — Not used
43 — Not used
44 20A** Driver side HID low beam
headlamp
45 30A** Driver seat
46 40A** Run/Start bus bar
47 30A** Air suspension – solenoids
48 20A** Passenger side HID low beam
headlamp
49 30A** Front wipers/washer
50 30A** PCM – bus bar
51 20A** Cargo power point
52 20A** Cigarette lighter
53 — Air suspension relay
54 — Starter relay
55 — Trailer tow connector relay (park
lamp)
56 — Trailer tow connector relay
(battery charge)
2007 Navigator(nav)
Owners Guide (post-2002-fmt)
USA(fus)
Roadside Emergencies
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•You may want to turn off the speed control in hilly terrain if
unnecessary shifting between the top gears occurs. Unnecessary
shifting of this type could result in reduced fuel economy.
•Warming up a vehicle on cold mornings is not required and may
reduce fuel economy.
•Resting your foot on the brake pedal while driving may reduce fuel
economy.
•Combine errands and minimize stop-and-go driving.
Maintenance
•Keep tires properly inflated and use only recommended size.
•Operating a vehicle with the wheels out of alignment will reduce fuel
economy.
•Use recommended engine oil. Refer toMaintenance product
specifications and capacitiesin this chapter.
•Perform all regularly scheduled maintenance items. Follow the
recommended maintenance schedule and owner maintenance checks
found inscheduled maintenance information.
Conditions
•Heavily loading a vehicle or towing a trailer may reduce fuel economy
at any speed.
•Carrying unnecessary weight may reduce fuel economy (as much as
1 mpg [0.4 km/L] is lost for every 400 lb [180 kg] of weight carried).
•Adding certain accessories to your vehicle (for example bug
deflectors, rollbars/light bars, running boards, ski/luggage racks) may
reduce fuel economy.
•Using fuel blended with alcohol may lower fuel economy.
•Fuel economy may decrease with lower temperatures during the first
8–10 miles (12–16 km) of driving.
•Driving on flat terrain offers improved fuel economy as compared to
driving on hilly terrain.
•Transmissions give their best fuel economy when operated in the top
cruise gear and with steady pressure on the gas pedal.
•Four-wheel-drive operation (if equipped) is less fuel efficient than
two-wheel-drive operation.
•Close windows for high speed driving.
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Owners Guide (post-2002-fmt)
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Maintenance and Specifications
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Lifestyle
Ash cup / smoker’s package
Cargo organization and management
Cross bars
Towing mirrors
Trailer hitches, wiring harnesses and accessories
Peace of mind
Mobile-Easehands-free communication system
Remote start
Vehicle security systems
Wheel locks
Not all accessories are available for all models.
For maximum vehicle performance, keep the following information in
mind when adding accessories or equipment to your vehicle:
•When adding accessories, equipment, passengers and luggage to your
vehicle, do not exceed the total weight capacity of the vehicle or of
the front or rear axle (GVWR or GAWR as indicated on the Safety
Compliance Certification label). Consult your authorized dealer for
specific weight information.
•The Federal Communications Commission (FCC) and Canadian Radio
Telecommunications Commission (CRTC) regulate the use of mobile
communications systems — such as two-way radios, telephones and
theft alarms - that are equipped with radio transmitters. Any such
equipment installed in your vehicle should comply with FCC or CRTC
regulations and should be installed only by a qualified service
technician.
•Mobile communications systems may harm the operation of your
vehicle, particularly if they are not properly designed for automotive
use.
•To avoid interference with other vehicle functions, such as anti-lock
braking systems, amateur radio users who install radios and antennas
onto their vehicle should not locate the Amateur Radio Antennas in
the area of the driver’s side hood.
•Electrical or electronic accessories or components that are added to
the vehicle by the authorized dealer or the owner may adversely affect
battery performance and durability.
2007 Navigator(nav)
Owners Guide (post-2002-fmt)
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Accessories
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