Maintenance under severe operating conditions
The maintenance intervals shown on the preceding pages are for normal
operating conditions. If the vehicle is mainly operated under severe driving
conditions as shown below, more frequent maintenance must be performed on the
following items as shown in the table.
Severe driving conditions
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Uniform tire quality grading
DOT (Department of Transportation) Quality
Grades: All passenger car tires must conform to
federal safety requirements in addition to these
grades.
Quality grades can be found where applicable on
the tire sidewall between tread shoulder and
maximum section width. For example:
Treadwear 200 ...