745
Maintenance
7. Uniform tire quality grading
Quality grades can be found where
applicable on the tire sidewall
between tread shoulder and maxi-
mum section width.
For example:
TREADWEAR 440
TRACTION A
TEMPERATURE A
Tread wear
The tread wear grade is a compara-
tive rating based on the wear rate of
the tire when tested under controlled
conditions on a specified govern-
ment test course. For example, a tire
graded 150 would wear one-and-a-
half times (1½) as well on the gov-
ernment course as a tire graded 100.
The relative performance of tires
depends upon the actual conditions
of their use, however, and may
depart significantly from the norm
due to variations in driving habits,
service practices and differences in
road characteristics and climate.Tires degrade over time, even when
they are not being used. Regardless
of the remaining tread, we recom-
mend that tires be replaced after
approximately six (6) years of nor-
mal service. Heat caused by hot cli-
mates or frequent high loading con-
ditions can accelerate the aging
process.
These grades are molded on the
side-walls of passenger vehicle tires.
The tires available as standard or
optional equipment on your vehicles
may vary with respect to grade.
Traction - AA, A, B & C
The traction grades, from highest to
lowest, are AA, A, B and C. Those
grades represent the tires ability to
stop on wet pavement as measured
under controlled conditions on spec-
ified government test surfaces of
asphalt and concrete. A tire marked
C may have poor traction perform-
ance.
The traction grade assigned to this
tire is based on straight-ahead brak-
ing traction tests, and does not
include acceleration, cornering,
hydroplaning, or peak traction char-
acteristics.
Specifications, Consumer information, Reporting safety defects
68
Recommended SAE viscosity
number
Always be sure to clean the area around
any filler plug, drain plug, or dipstick
before checking or draining any lubricant.
This is especially important in dusty or
sandy areas and when the vehicle is
used on unpaved roads. Cleaning the
plug and dipstick areas will prevent dirt
and grit from entering the engine and
other mechanisms that could be dam-
aged.Engine oil viscosity (thickness) has an
effect on fuel economy and cold weather
operation (engine start and engine oil
flowability). Lower viscosity engine oils
can provide better fuel economy and cold
weather performance, however, higher
viscosity engine oils are required for sat-
isfactory lubrication in hot weather. Using
oils of any viscosity other than those rec-
ommended could result in engine dam-
age.
When choosing an oil, consider the range
of temperature your vehicle will be oper-
ated in before the next oil change.
Proceed to select the recommended oil
viscosity from the chart.
Temperature Range for SAE Viscosity Numbers
Temperature
Gasoline
Engine Oil *
1
°C
(°F)-30 -20 -10 0 10 20 30 40 50 -10 0 20 40 60 80 100 120
1. For better fuel economy, it is recommended to use the engine oil of
a viscosity grade SAE 5W-20 (API SM / ILSAC GF-4). However, if
the engine oil is not available in your country, select the proper
engine oil using the engine oil viscosity chart.
10W-30
5W-20, 5W-30