
When to Check
Check your tires once a month or more.
Also, check the tire pressure of the spare tire.
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t tell if your tires are properly in ated
simply by looking at them. Radial tires may look
properly in ated even when they’re underin ated. Check
the tire’s in ation pressure when the tires are cold.
Cold means your vehicle has been sitting for at least
three hours or driven no more than 1 mile (1.6 km).
Remove the valve cap from the tire valve stem. Press
the tire gage rmly onto the valve to get a pressure
measurement. If the cold tire in ation pressure matches
the recommended pressure on the tire and loading
information label, no further adjustment is necessary.
If the pressure is low, add air until you reach the
recommended amount.
If you over ll the tire, release air by pushing on the
metal stem in the center of the tire valve. Recheck the
tire pressure with the tire gage.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and moisture.
Dual Tire Operation
When the vehicle is new, or whenever a wheel, wheel
bolt or wheel nut is replaced, check the wheel nut torque
after 100, 1,000 and 6,000 miles (160, 1 600 and
10 000 km) of driving. For proper wheel nut tightening
information, see “Removing the Flat Tire and Installing
the Spare Tire” later in this section, underChanging
a Flat Tire on page 5-76. Also see “Wheel Nut Torque”
underCapacities and Speci cations on page 5-106.
The outer tire on a dual wheel setup generally wears
faster than the inner tire. Your tires will wear more
evenly and last longer if you rotate the tires periodically.
SeeTire Inspection and Rotation on page 5-68. Also
seeScheduled Maintenance on page 6-4.
{CAUTION:
If you operate your vehicle with a tire that is
badly underin ated, the tire can overheat. An
overheated tire can lose air suddenly or catch
re. You or others could be injured. Be sure all
tires (including the spare) are properly in ated.
SeeTires on page 5-58andIn ation - Tire Pressure on
page 5-66for more information on proper tire in ation.
5-67

Tire Inspection and Rotation
Tires should be rotated every 5,000 to 8,000 miles
(8 000 to 13 000 km).
Any time you notice unusual wear, rotate your tires as
soon as possible and check wheel alignment. Also
check for damaged tires or wheels. SeeWhen It Is Time
for New Tires on page 5-69andWheel Replacement
on page 5-72for more information.
Make sure the spare tire is stored securely. Push, pull,
and then try to rotate or turn the tire. If it moves,
use the ratchet/wheel wrench to tighten the cable. See
Changing a Flat Tire on page 5-76.
If your vehicle has dual rear wheels, also seeDual Tire
Operation on page 5-67.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The rst rotation
is the most important. SeeScheduled Maintenance
on page 6-4.If your vehicle has single rear wheels, always use one
of the correct rotation patterns shown here when rotating
your vehicle’s tires.
If your vehicle has dual rear wheels, always use one of
the correct rotation patterns shown here when rotating
your tires.
5-68

The tools you will be using include the jack (A), jack
handle extension (B), jack handle (C), wheel wrench (D)
and the ratchet (E).
Your spare tire is stored underneath the rear of your
vehicle. You will use the wheel wrench (D) and the
ratchet (E) to lower the spare tire.The ratchet has a DOWN side and an UP side.
Attach the wheel wrench
and ratchet, with the
DOWN side facing you.
The wheel wrench
has a socket end and a
at chisel end.
Put the at chisel end of the wheel wrench on an angle
through the hole between the body and the bumper.
Be sure the at end connects into the hoist shaft.
5-78

Turn the ratchet counterclockwise to lower the spare tire
to the ground. If the spare tire does not lower to the
ground, the secondary latch is engaged causing the tire
not to lower. See “Secondary Latch System” later in
this section.When the tire has been lowered, pull the tire toward you
so you can reach the tire retainer and pull it up
through the wheel opening.
If you have a vehicle which was completed from a cab
and chassis, refer to the information from the body
supplier/installer.
The spare tire is a full-size tire, like the other tires on
your vehicle.
Notice:If you drive away before the spare tire or
secondary latch system cable has been reinstalled,
you could damage your vehicle. Always reinstall
this cable before driving your vehicle.
5-79

8. Lower the jack by turning the ratchet
counterclockwise. Keep lowering the jack until the
spare tire slides off the jack or is hanging by
the cable.
9. Disconnect the jack handle from the jack and
carefully remove the jack. Use one hand to
push against the spare while rmly pulling the jack
out from under the spare tire with the other
hand.
If the spare tire is hanging from the cable, slide the
ratchet onto the wheel wrench and insert the
wheel wrench into the hoist shaft hole above the
bumper. Turn the wheel wrench counterclockwise to
lower the spare the rest of the way. Be sure the
DOWN mark on the ratchet is facing you.
10. Tilt the retainer at the end of the cable and pull it
through the wheel opening. Pull the tire out from
under the vehicle.
11. If the cable is hanging under the vehicle, turn the
wheel wrench in the hoist shaft hole in the bumper
clockwise to raise the cable back up.Have the hoist assembly inspected as soon as you can.
You will not be able to store a spare or at tire using
the hoist assembly until it has been repaired or replaced.
To continue changing the at tire, return to Step 4 of
“Removing the Flat Tire and Installing the Spare
Tire” later in this section.
Removing the Wheel Covers
If your vehicle has plastic wheel nut caps, loosen them
by turning the wheel wrench counterclockwise. The
wheel nut caps are designed to remain with the center
cap. Remove the center cap.
If the wheel has a smooth center piece, place the chisel
end of the wheel wrench in the slot on the wheel and
gently pry it out.
5-83

Removing the Flat Tire and Installing
the Spare Tire
1. With the DOWN side facing you, use the ratchet
and wheel wrench to loosen all the wheel nuts.
Do not remove them yet.
2. Assemble the jack and tools for a front or rear at
as follows:
Front Flat:Assemble the jack (A) together with the
jack handle (B) and ratchet (C) as shown. Be
sure that the ratchet has the UP mark facing you.Rear Flat:Assemble the jack (A) together with the
jack handle (B), jack handle extension (C) and
ratchet (D) as shown. Be sure that the ratchet has
the UP mark facing you. To assemble the jack
handle and jack handle extension, use the art and
text following.
Connect the jack handle (B) and jack handle
extension (C) together and press the retention clip
(arrow) so it engages. Front Position
Rear Position
5-84