(q) During any maintenance, if a power washer is used
to clean mud and dirt from the underbody, care should
be taken to not directly spray the transfer case output
seals. High pressure water can overcome the seals and
contaminate the transfer case fluid. Contaminated fluid
will decrease the life of the transfer case and should be
replaced.
(r) Change transfer case fluid if the vehicle is mainly
driven under one or more of these conditions:
− In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
− In hilly or mountainous terrain.
− When doing frequent trailer towing.
− Uses such as high performance operation or taxi,
police, or delivery service.
Owner Checks and Services
These owner checks and services should be performed
at the intervals specified to help ensure vehicle safety,
dependability, and emission control performance. Your
dealer/retailer can assist with these checks and services.
Be sure any necessary repairs are completed at once.
Whenever any fluids or lubricants are added to the
vehicle, make sure they are the proper ones, as shown
in Recommended Fluids and Lubricants on page 6-14.
At Each Fuel Fill
It is important to perform these underhood checks at
each fuel fill.
Engine Oil Level Check
Notice: It is important to check the engine oil
regularly and keep it at the proper level. Failure to
keep the engine oil at the proper level can cause
damage to the engine not covered by the vehicle
warranty.
Check the engine oil level and add the proper oil if
necessary. See Engine Oil on page 5-18.
Coolant Level Check
Check the engine coolant level and, on CTS-V models,
check the intercooler coolant level. Add DEX-COOL
®
coolant mixture if necessary. See Engine Coolant
on page 5-31.
Windshield Washer Fluid Level Check
Check the windshield washer fluid level in the windshield
washer fluid reservoir and add the proper fluid if
necessary.
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