Cadillac CTS 2018 Owner's Manual page 321

320 SERVICE AND MAINTENANCE
Road Test. Check all systems for
correct function/performance.
To maintain air conditioning
efficiency, have an authorised
repairer check the system at least
once each year.
Automatic transmission shift lock
control function check.
Parking brake and automatic
P (Park) mechanism check.
Underbody flushing service.
Tyre sealant and compressor kit (if
equipped with tyre sealant and
compressor kit), check sealant
expiration date.
Inspect sunroof track and seal,
if equipped. See Sunroof 0 51.
Additional Maintenance Every
30 000 km or 2 Years
In addition to the items listed under
"Inspection Every 15 000 km or 1
Year" the following items should be
carried out every 30,000 km or 2 years
(whichever occurs first):
Passenger compartment air filter
replace (if applicable). More
frequent passenger compartment
air filter replacement may be
needed if driving in areas with
heavy traffic, poor air quality, high
dust levels, or environmental
allergens. Passenger compartment
air filter replacement may also be
needed if there is reduced airflow,
window misting, or odours. Your
GM retailer can help determine
when to replace the filter.
Engine air filter replacement.
If driving in dusty conditions,
inspect the filter at each oil
change or more often as needed.
Note: All vehicles with rear-wheel
drive change driveline axle oil
every 30 000 km, if vehicle is used for
towing purposes.
Replace Every 2 Years
Note: All vehicles with rear-wheel
drive change driveline axle oil
every 30 000 km, if vehicle is used for
towing purposes.
Additional Maintenance Every
60 000 km
Replace brake fluid. Or every
two years, whichever occurs first.
Additional Maintenance Every
72 000 km
All-wheel-drive vehicles only:
Transfer case fluid change (severe
service) for vehicles mainly driven
in heavy city traffic in hot
weather, in hilly or mountainous
terrain, when frequently towing a
trailer, or when used for taxi,
police, or delivery service. During
any maintenance, if a power
washer is used to clean mud and
dirt from the underbody, do not
directly power wash the transfer
case and/or front/rear axle output
seals. High pressure water can
overcome the seals and
contaminate the fluid.
Contaminated fluid will decrease
the life of the transfer case and/or
drive axles and should be replaced.
Automatic transmission fluid and
filter change (severe service) for
vehicles mainly driven in heavy