winter tires JEEP COMPASS 2008 1.G Owners Manual

check tire pressure. Do not make a visual judgement
when determining proper inflation. Radial tires may look
properly inflated even when they are under inflated.
CAUTION!
After inspecting or adjusting the tire pressure, al-
ways reinstall the valve stem cap (if equipped). This
will prevent moisture and dirt from entering the
valve stem, which could damage the valve stem.
Inflation pressures specified on the placard are always
ªcold tire inflation pressure.º Cold tire inflation pressure
is defined as the tire pressure after the vehicle has not
been driven for at least 3 hours, or driven less than 1 mile
(1 km) after a 3 hour period. The cold tire inflation
pressure must not exceed the maximum inflation pres-
sure molded into the tire sidewall.Check tire pressures more often if subject to a wide range
of outdoor temperatures, as tire pressures vary with
temperature changes.
Tire pressures change by approximately 1 psi (7 kPa) per
12 ÉF (7 ÉC) of air temperature change. Keep this in mind
when checking tire pressure inside a garage, especially in
the winter.
Example: If garage temperature = 68 ÉF (20 ÉC) and the
outside temperature = 32 ÉF (0 ÉC) then the cold tire
inflation pressure should be increased by 3 psi (21 kPa),
which equals 1 psi (7 kPa) for every 12 ÉF (7 ÉC) for this
outside temperature condition.
Tire pressure may increase from 2 to 6 psi (13 to 40 kPa)
during operation. DO NOT reduce this normal pressure
build up or your tire pressure will be too low.
258 STARTING AND OPERATING

SNOW TIRES
Some areas of the country require the use of snow tires
during winter. Standard tires are of the all season type
and satisfy this requirement as indicated by the M+S
designation on the tire sidewall.
If you need snow tires, select tires equivalent in size and
type to the original equipment tires. Use snow tires only
in sets of 4, failure to do so may adversely affect the
safety and handling of your vehicle.
Snow tires generally have lower speed ratings than what
was originally equipped with your vehicle and should
not be operated at sustained speeds over 75 mph (120
km/h).
FUEL REQUIREMENTS
GASOLINE ENGINES
Your vehicle is designed to meet all emis-
sion regulations and provide excellent fuel
economy when using high quality regular
unleaded gasoline with an octane rating of
87. The use of premium gasoline is not
recommended. The use of premium gaso-
line will provide no benefit over high quality regular
gasolines, and in some circumstances, may result in
poorer performance.
Light spark knock at low engine speeds is not harmful to
your engine. However, continued heavy spark knock at
high speeds can cause damage and immediate service is
required.
Poor quality gasoline can cause problems such as hard
starting, stalling and hesitations. If you experience these
STARTING AND OPERATING 275
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