Western Star 47X 2020, Maintenance Manual

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Determining Scheduled
Maintenance Intervals
Performing regular maintenance on your Western
Star vehicle will help ensure that your vehicle deliv-
ers safe reliable service and optimum performance
for years to come. Failure to follow a regular mainte-
nance program can result in inefficient operation and
unscheduled down time.
To determine the correct maintenance intervals for
your vehicle you must first determine the type of ser-
vice or conditions the vehicle will be operating in.
Generally, over-the-road vehicles operate under con-
ditions that fall within one of the two types of service
described. Before placing your new vehicle in ser-
vice, determine the type of service (Service Schedule
I or II) that applies to the intended use of the vehicle.
After determining the vehicle’s type of service, refer
to the service schedule table or the vehicle mainte-
nance schedule table, to determine how often main-
tenance should be performed.
When the vehicle reaches the distance given for a
maintenance interval, see the Maintenance Interval
Operation Table for a list of the maintenance opera-
tions to be performed at that maintenance interval.
Use the maintenance operation reference numbers to
find detailed instructions in the manual on each op-
eration.
Types of Service
Service Schedule I (short-haul transport) applies to
vehicles that annually travel less than 60,000 miles
(100 000 kilometers) and operate under normal con-
ditions. Examples of Schedule I usage are: operation
primarily in cities and densely populated areas; local
transport with infrequent freeway travel; or high per-
centage of stop-and-go travel.
Service Schedule II (long-haul transport) is for ve-
hicles that annually travel more than 60,000 miles
(100 000 kilometers) with minimal city or stop-and-go
operation. Examples of Schedule II usage are: re-
gional delivery that is mostly freeway miles; interstate
transport; or any road operation with high annual
mileage.
NOTE: Maintenance instructions in this manual
are based on average vehicle use and normal
operating conditions. Unusual vehicle operating
conditions may require service at more frequent
intervals.
General Information
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