
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/14/17
SERVICE AND MAINTENANCE 393
Footnotes—Maintenance Schedule
Additional Required Services -
Normal
(1) Vehicles with different size front
and rear tires do not have tire
rotation. See Tire Rotation0353.
(2) Or every two years, whichever
comes first. 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 airf low, window
fogging, or odors. Your GM dealer can
help determine when to replace the
filter.
(3) Visually check all fuel and vapor
lines and hoses for proper attachment,
connection, routing, and condition.
(4) Or every four years, whichever
comes first. If driving in dusty
conditions, inspect the filter at each
oil change or more often as needed. (5)
Or every five years, whichever
comes first.
See Cooling System (Gasoline Only)
0 312 orCooling System (PLUG-IN
Only) 0316.
(6) 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 transfer case fluid. Contaminated
fluid will decrease the life of the
transfer case and/or axles and should
be replaced.
(7) Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage; replace,
if needed.
(8) Replace brake fluid every five
years for DOT 3 fluid or every three
years for DOT 4 fluid. See Brake Fluid
0 323.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/14/17
394 SERVICE AND MAINTENANCE
Maintenance Schedule
Additional Required Services -
Severe12 000 km/7,500 mi
24 000 km/15,000 mi
36 000 km/22,500 mi
48 000 km/30,000 mi
60 000 km/37,500 mi
72 000 km/45,000 mi
84 000 km/52,500 mi
96 000 km/60,000 mi
108 000 km/67,500 mi
120 000 km/75,000 mi
132 000 km/82,500 mi
144 000 km/90,000 mi
156 000 km/97,500 mi
168 000 km/105,000 mi
180 000 km/112,500 mi
192 000 km/120,000 mi
204 000 km/127,500 mi
216 000 km/135,000 mi
228 000 km/142,500 mi
240 000 km/150,000 mi
Rotate tires, if recommended for the vehicle, and
perform Required Services. Check engine oil level
and oil life percentage. Change engine oil and filter,
if needed. (1)@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
Replace passenger compartment air filter. (2)@ @@@@@
Inspect evaporative control system. (3)@ @@
Replace engine air cleaner filter. (4)@@@
Replace spark plugs. Inspect spark plug wires. (2.0L
and 3.0L Twin Turbo Engines)@ @
Replace spark plugs. Inspect spark plug wires. (3.6L
Engine Only)@
Change automatic transmission fluid and filter.@@@
Change transfer case fluid, if equipped with
AWD. (5)@@@
Change rear axle fluid.@@@
Change front axle fluid, if equipped with AWD.@@@
Drain and fill engine cooling system and Power
Electronics cooling system. (6)@
Visually inspect accessory drive belts. (7)@
Replace brake fluid. (8)

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/14/17
SERVICE AND MAINTENANCE 395
Footnotes—Maintenance Schedule
Additional Required Services -
Severe
(1) Vehicles with different size front
and rear tires do not have tire
rotation. See Tire Rotation0353.
(2) Or every two years, whichever
comes first. 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 airf low, window
fogging, or odors. Your GM dealer can
help determine when to replace the
filter.
(3) Visually check all fuel and vapor
lines and hoses for proper attachment,
connection, routing, and condition.
(4) Or every four years, whichever
comes first. If driving in dusty
conditions, inspect the filter at each
oil change or more often as needed.
(5) 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 transfer case fluid. Contaminated
fluid will decrease the life of the
transfer case and/or axles and should
be replaced.
(6)
Or every five years, whichever
comes first.
See Cooling System (Gasoline Only)
0 312 orCooling System (PLUG-IN
Only) 0316.
(7) Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage; replace,
if needed.
(8) Replace brake fluid every five
years for DOT 3 fluid or every three
years for DOT 4 fluid. See Brake Fluid
0 323.Special Application
Services
.
Severe Commercial Use Vehicles
Only: Lubricate chassis
components every oil change.
. Have underbody flushing service
performed. See "Underbody
Maintenance" in Exterior Care
0 380.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/14/17
SERVICE AND MAINTENANCE 399
Recommended Fluids, Lubricants, and Parts
Recommended Fluids and Lubricants
UsageFluid/Lubricant
Automatic Transmission DEXRON-HP Automatic Transmission Fluid (GM Part No. 19331925, in Canada 19300537).
Engine Coolant (Gasoline Only Vehicles) 50/50 mixture of clean drinkable water and use only DEX-COOL Coolant. Engine Coolant, High Voltage Battery,
and Power Electronics Cooling System (PLUG-IN Only Vehicles) Use Only Premix DEX-COOL Coolant (GM Part No. 12378390, in
Canada 10953456).
See
Cooling System (Gasoline Only) 0312 orCooling System (PLUG-IN Only)
0 316.
Engine Oil Engine oil meeting the dexos1 specification of the proper SAE viscosity grade.
ACDelco dexos1 is recommended. See Engine Oil0307.
Hood Latch Assembly, Pivots, Spring Anchor, and Release Pawl Lubriplate Lubricant Aerosol (GM Part No. 89021668, in Canada 89021674) or
lubricant meeting requirements of NLGI #2, Category LB or GC-LB.
Hydraulic Brake System (Gasoline Only) DOT 3 Hydraulic Brake Fluid (GM Part No. 19299818, in Canada 19299819).
Hydraulic Brake System (PLUG-IN Only) DOT 4 Hydraulic Brake Fluid (GM Part No. 19299570, in Canada 19299571). Key Lock Cylinders, Hood and Door Hinges Multi-Purpose Lubricant, Superlube (GM Part No. 12346241, in
Canada 10953474).
Rear Axle SAE 75W-90 Synthetic Axle Lubricant (GM Part No. 88863089, in
Canada 88863090) meeting GM Specification 9986285.
Rear Axle/Front Axle (All-Wheel Drive) SAE 75W-90 Synthetic Axle Lubricant (GM Part No. 88863089, in Canada 88863090).

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/14/17
404 TECHNICAL DATA
Vehicle Data
Capacities and Specifications
The following approximate capacities are given in metric and English conversions. SeeRecommended Fluids and Lubricants
0 399 for more information.
Application Capacities
Metric English
Air Conditioning Refrigerant For the air conditioning system refrigerant type and charge amount, see the refrigerant label under thehood. See your dealer for more information.
Brake Fluid 0.4 L 0.4 qt
Cooling System –Engine
2.0L L4 Engine 8.6 L 9.1 qt
2.0L L4 Engine with Rear A/C 10.3 L 10.9 qt
2.0L L4 PLUG–IN Engine 9.8 L 10.4 qt
2.0L L4 PLUG–IN Engine –Power Electronics 4.0 L 4.2 qt
2.0L L4 PLUG–IN Engine –RESS 3.1 L 3.3 qt
3.0L V6 Engine 10.6 L 11.2 qt
3.0L V6 Engine with Rear A/C 12.3 L 13.0 qt
3.0L V6 Engine with Rear A/C and Auxiliary Radiator 13.2 L 13.9 qt
3.0L V6 Engine with Auxiliary Radiator 11.5 L 12.2 qt

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/14/17
434 INDEX
Child Restraints (cont'd)Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
Cigarette Lighter . . . . . . . . . . . . . . . . . . . . 125
Circuit Breakers . . . . . . . . . . . . . . . . . . . . . 331
Cleaning Exterior Care . . . . . . . . . . . . . . . . . . . . . . 380
Interior Care . . . . . . . . . . . . . . . . . . . . . . 384
Climate Control Systems Automatic . . . . . . . . . . . . . . . . . . . . 191, 197
Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Cluster, Instrument . . . . . . . . . . . .127, 130
Collision Damage Repair . . . . . . . . . . . 414
Compact Spare Tire . . . . . . . . . . . . . . . . . 373
Compartments Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Compass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Compressor Kit, Tire Sealant . . . . . . . 362
Connections OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 423
Control Traction and ElectronicStability . . . . . . . . . . . . . . . . . . . . . . . . . . 239
Control of a Vehicle . . . . . . . . . . . . . . . . 207
Convenience Net . . . . . . . . . . . . . . . . . . . . 117
Convex Mirrors . . . . . . . . . . . . . . . . . . . . . . 54 Coolant
Engine Temperature Gauge . . . . . . 139
Engine Temperature Warning
Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
Cooling . . . . . . . . . . . . . . . . . . . . . . . . .191, 197
Cooling System . . . . . . . . . . . . . . . .312, 316
Courtesy Lamps . . . . . . . . . . . . . . . . . . . . . 187
Courtesy Transportation Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . 413
Cruise Control . . . . . . . . . . . . . . . . . . . . . . . 242 Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
Cruise Control, Adaptive . . . . . . . . . . . 245
Customer Assistance . . . . . . . . . . . . . . . 410 Offices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 410
Text Telephone (TTY) Users . . . . . 410
Customer Information
Service Publications OrderingInformation . . . . . . . . . . . . . . . . . . . . . . 416
Customer Satisfaction Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . 408
D
Damage Repair, Collision . . . . . . . . . . . 414
Danger, Warning, and Caution . . . . . . . . 2
Data CollectionInfotainment System . . . . . . . . . . . . . 420
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 420 Data Recorders, Event . . . . . . . . . . . . . . 419
Daytime Running Lamps (DRL) . . . 185
Defensive Driving . . . . . . . . . . . . . . . . . . . 207
Delayed Charging Override . . . . . . . . . 275
Delayed Locking . . . . . . . . . . . . . . . . . . . . . 45
Diagnostics
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 425
Distracted Driving . . . . . . . . . . . . . . . . . . 206
Dome Lamps . . . . . . . . . . . . . . . . . . . . . . . . 187
Door Ajar Light . . . . . . . . . . . . . . . . . . . . . . . . . 152
Delayed Locking . . . . . . . . . . . . . . . . . . . . 45
Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Power Locks . . . . . . . . . . . . . . . . . . . . . . . . . 45
Rear Seat Pass-Through . . . . . . . . . . . . 77
Drive Belt Routing, Engine . . . . . . . . . 406
Drive Systems
All-Wheel Drive . . . . . . . . . . . . . . 234, 326
Driver Assistance Systems . . . . . . . . . 253
Driver Information Center (DIC) . . . . . . . . . . . . . . . . . . . . . . . 162
Driver Mode Control . . . . . . . . . . . . . . . . 241
Driver Selected Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226
Driving
Assistance Systems . . . . . . . . . . . . . . . 260
Characteristics andTowing Tips . . . . . . . . . . . . . . . . . . . . . 290

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/14/17
INDEX 435
Driving (cont'd)Defensive . . . . . . . . . . . . . . . . . . . . . . . . . . 207
Drunk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207
For Better Fuel Economy . . . . . . . . . . . 32
Hill and Mountain Roads . . . . . . . . 211
If the Vehicle is Stuck . . . . . . . . . . . . 212
Loss of Control . . . . . . . . . . . . . . . . . . . . 209
Off-Road Recovery . . . . . . . . . . . . . . . . 209
Vehicle Load Limits . . . . . . . . . . . . . . 213
Wet Roads . . . . . . . . . . . . . . . . . . . . . . . . . 210
Winter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211
Winter Mode Light . . . . . . . . . . . . . . . 146
Driving for Better Energy Efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
E
Electric Parking Brake . . . . . . . . . . . . . . 235
Electric Parking Brake Light . . . . . . . 145
Electrical Equipment, Add-On . . . . . 295
Electrical Requirements for
Battery Charging . . . . . . . . . . . . . . . . . . 285
Electrical System Engine Compartment FuseBlock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 332
Fuses and Circuit Breakers . . . . . . . 331
Instrument Panel Fuse Block . . . . 335
Overload . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337 Emergency
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 422
Energy Efficiency Driving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Energy Information . . . . . . . . . . . . . . . . . 161
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . . . 311
Check Light (Malfunction
Indicator) . . . . . . . . . . . . . . . . . . . . . . . . 143
Compartment Overview . . . . . . . . . . 300
Coolant Temperature Gauge . . . . . 139
Coolant Temperature Warning Light . . . . . . . . . . . . . . . . . . . 149
Cooling System . . . . . . . . . . . . . . 312, 316
Drive Belt Routing . . . . . . . . . . . . . . . . 406
Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230
Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223
Oil Life System . . . . . . . . . . . . . . . . . . . . 309
Oil Pressure Gauge . . . . . . . . . . . . . . . . 137
Oil Pressure Light . . . . . . . . . . . . . . . . . 149
Overheating . . . . . . . . . . . . . . . . . . . . . . . 321
Power Messages . . . . . . . . . . . . . . . . . . 169
Running While Parked . . . . . . . . . . . 230
Starting . . . . . . . . . . . . . . . . . . . . . . . 218, 221
Engine Oil
Temperature Gauge . . . . . . . . . . . . . . . 138
Engine Unavailable Out of Fuel . . . . . . . . . . . . . . . . . . . . . . . . 227 Entry Lighting . . . . . . . . . . . . . . . . . . . . . . 188
Equipment, Towing . . . . . . . . . . . . . . . . . 294
Event Data Recorders . . . . . . . . . . . . . . 419
Exit Lighting . . . . . . . . . . . . . . . . . . . . . . . . 189
Extended Parking . . . . . . . . . . . . . . . . . . . 226
Extender, Seat Belt . . . . . . . . . . . . . . . . . . 83
Exterior Lamp Controls . . . . . . . . . . . . 183
Exterior Lamps Off Reminder . . . . . . 185
Exterior Lighting Battery Saver . . . . 189
F
Features
Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Filter, Engine Air Cleaner . . . . . . . . . . . . . . . . 311
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . 185
Flashers, Hazard Warning . . . . . . . . . . 186
Flat Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 360 Changing . . . . . . . . . . . . . . . . . . . . . . . . . . 368
Floor Mats . . . . . . . . . . . . . . . . . . . . . . . . . . . 387
Fluid Automatic Transmission . . . . . . . . . 310
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323
Washer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322
Folding Mirrors . . . . . . . . . . . . . . . . . . . . . . 55
Forward Automatic Braking . . . . . . . . 262
Forward Collision Alert (FCA) System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260