2018 GMC SIERRA DENALI automatic transmission

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 3091500/2500/3500 Series Pickups – SAE J2807 Compliant
Vehicle Axle Ratio Maximum Trailer
Weight (c) GCWR (a)
1500 Series 2WD Regular Cab Standard Box
4.3L V6 3.23 2 722 kg (6,000 lb) 4 990 kg (11,000 lb)
4.3L V6 4.10 2 087 kg (4,600 lb) 4 309 kg (9,500 lb)
5.3L V8 3.08 3 130 kg (6,900 lb) 5 443 kg (12,000 lb)
5.3L V8 3.42 4 037 kg (8,900 lb) 6 350 kg (14,000 lb)
1500 Series 2WD Double Cab Standard Box
4.3L V6 3.23 2 540 kg (5,600 lb) 4 990 kg (11,000 lb)
5.3L V8 3.08 2 903 kg (6,400 lb) 5 443 kg (12,000 lb)
5.3L V8, 6-speed automatic
transmission 3.42 4 264 kg (9,400 lb) 6 804 kg (15,000 lb)
5.3L V8, 8-speed automatic
transmission – Conventional
Trailer 3.42 4 264 kg (9,400 lb) 6 804 kg (15,000 lb)
5.3L V8, 8-speed automatic
transmission – Gooseneck/
Fifth-Wheel Trailer 3.42 4 128 kg (9,100 lb) 6 804 kg (15,000 lb)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
310 Driving and Operating 1500/2500/3500 Series Pickups – SAE J2807 Compliant
Vehicle Axle Ratio Maximum Trailer
Weight (c) GCWR (a)
5.3L V8, 8-speed automatic
transmission with Enhanced
Towing Package – Conventional
Trailer 3.42 5 035 kg (11,100 lb) 7 575 kg (16,700 lb)
5.3L V8, 8-speed automatic
transmission with Enhanced
Towing Package – Gooseneck/
Fifth-Wheel Trailer 3.42 4 990 kg (11,000 lb) 7 575 kg (16,700 lb)
5.3L V8 – Conventional Trailer 3.73 5 035 kg (11,100 lb) 7 575 kg (16,700 lb)
5.3L V8 – Gooseneck/Fifth-Wheel
Trailer 3.73 4 990 kg (11,000 lb) 7 575 kg (16,700 lb)
6.2L V8 – Conventional Trailer 3.23 4 264 kg (9,400 lb) 6 804 kg (15,000 lb)
6.2L V8 – Gooseneck/Fifth-Wheel
Trailer 3.23 4 082 kg (9,000 lb) 6 804 kg (15,000 lb)
6.2L V8 – Conventional Trailer 3.42 5 670 kg (12,500 lb) 8 255 kg (18,200 lb)
6.2L V8 – Gooseneck/Fifth-Wheel
Trailer 3.42 5 262 kg (11,600 lb) 8 255 kg (18,200 lb)
1500 Series 2WD Crew Cab Standard Box
5.3L V8 3.08 2 858 kg (6,300 lb) 5 443 kg (12,000 lb)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 3111500/2500/3500 Series Pickups – SAE J2807 Compliant
Vehicle Axle Ratio Maximum Trailer
Weight (c) GCWR (a)
5.3L V8 – Conventional Trailer 3.42 4 218 kg (9,300 lb) 6 804 kg (15,000 lb)
5.3L V8, 6-speed automatic
transmission – Gooseneck/
Fifth-Wheel Trailer 3.42 3 856 kg (8,500 lb) 6 804 kg (15,000 lb)
5.3L V8, 8-speed automatic
transmission – Gooseneck/
Fifth-Wheel Trailer 3.42 3 674 kg (8,100 lb) 6 804 kg (15,000 lb)
5.3L V8, 8-speed automatic
transmission with Enhanced
Towing Package – Conventional
Trailer 3.42 4 944 kg (10,900 lb) 7 575 kg (16,700 lb)
5.3L V8, 8-speed automatic
transmission with Enhanced
Towing Package – Gooseneck/
Fifth-Wheel Trailer 3.42 4 808 kg (10,600 lb) 7 575 kg (16,700 lb)
5.3L V8 – Conventional Trailer 3.73 4 990 kg (11,000 lb) 7 575 kg (16,700 lb)
5.3L V8 – Gooseneck/Fifth-Wheel
Trailer 3.73 4 853 kg (10,700 lb) 7 575 kg (16,700 lb)
6.2L V8 – Conventional Trailer 3.23 4 218 kg (9,300 lb) 6 804 kg (15,000 lb)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
312 Driving and Operating 1500/2500/3500 Series Pickups – SAE J2807 Compliant
Vehicle Axle Ratio Maximum Trailer
Weight (c) GCWR (a)
6.2L V8 – Gooseneck/Fifth-Wheel
Trailer 3.23 3 765 kg (8,300 lb) 6 804 kg (15,000 lb)
6.2L V8 – Conventional Trailer 3.42 5 398 kg (11,900 lb) 8 029 kg (17,700 lb)
6.2L V8 – Gooseneck/Fifth-Wheel
Trailer 3.42 4 763 kg (10,500 lb) 8 029 kg (17,700 lb)
1500 Series 2WD Crew Cab Short Box (b)
4.3L V6 3.23 2 495 kg (5,500 lb) 4 990 kg (11,000 lb)
5.3L V8 3.08 2 903 kg (6,400 lb) 5 443 kg (12,000 lb)
5.3L V8, 6-speed automatic
transmission 3.42 4 264 kg (9,400 lb) 6 804 kg (15,000 lb)
5.3L V8, 8-speed automatic
transmission 3.42 4 218 kg (9,300 lb) 6 804 kg (15,000 lb)
5.3L V8, 8-speed automatic
transmission with Enhanced
Towing Package 3.42 4 990 kg (11,000 lb) 7 575 kg (16,700 lb)
5.3L V8 3.73 4 990 kg (11,000 lb) 7 575 kg (16,700 lb)
6.2L V8 3.23 4 218 kg (9,300 lb) 6 804 kg (15,000 lb)
6.2L V8 3.42 5 670 kg (12,500 lb) 8 255 kg (18,200 lb)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
314 Driving and Operating 1500/2500/3500 Series Pickups – SAE J2807 Compliant
Vehicle Axle Ratio Maximum Trailer
Weight (c) GCWR (a)
5.3L V8 3.08 2 812 kg (6,200 lb) 5 443 kg (12,000 lb)
5.3L V8 – Gooseneck/Fifth Wheel 3.08 2 767 kg (6,100 lb) 5 443 kg (12,000 lb)
5.3L V8 – Conventional Trailer 3.42 4 173 kg (9,200 lb) 6 804 kg (15,000 lb)
5.3L V8 – Gooseneck/Fifth Wheel 3.42 4 082 kg (9,000 lb) 6 804 kg (15,000 lb)
5.3L V8, 8-speed automatic
transmission with Enhanced
Towing Package 3.42 4 899 kg (10,800 lb) 7 575 kg (16,700 lb)
5.3L V8 3.73 4 899 kg (10,800 lb) 7 575 kg (16,700 lb)
6.2L V8 – Conventional Trailer 3.23 4 128 kg (9,100 lb) 6 804 kg (15,000 lb)
6.2L V8 – Gooseneck/Fifth-Wheel
Trailer 3.23 3 901 kg (8,600 lb) 6 804 kg (15,000 lb)
6.2L V8 – Conventional Trailer 3.42 5 352 kg (11,800 lb) 8 029 kg (17,700 lb)
6.2L V8 – Gooseneck/Fifth-Wheel
Trailer 3.42 4 990 kg (11,000 lb) 8 029 kg (17,700 lb)
1500 Series 4WD Crew Cab Standard Box
5.3L V8 – Conventional Trailer 3.08 2 767 kg (6,100 lb) 5 443 kg (12,000 lb)
5.3L V8 – Gooseneck/Fifth-Wheel
Trailer 3.08 2 722 kg (6,000 lb) 5 443 kg (12,000 lb)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 3151500/2500/3500 Series Pickups – SAE J2807 Compliant
Vehicle Axle Ratio Maximum Trailer
Weight (c) GCWR (a)
5.3L V8 – Conventional Trailer 3.42 4 128 kg (9,100 lb) 6 804 kg (15,000 lb)
5.3L V8 – Gooseneck/Fifth-Wheel
Trailer 3.42 3 674 kg (8,100 lb) 6 804 kg (15,000 lb)
5.3L V8 – 8-speed automatic
transmission with Enhanced
Towing Package - Conventional
Trailer 3.42 4 853 kg (10,700 lb) 7 575 kg (16,700 lb)
5.3L V8, 8-speed automatic
transmission with Enhanced
Towing Package – Gooseneck/
Fifth Wheel Trailer 3.42 4 627 kg (10,200 lb) 7 575 kg (16,700 lb)
5.3L V8 – Conventional Trailer 3.73 4 853 kg (10,700 lb) 7 575 kg (16,700 lb)
5.3L V8 – Gooseneck/Fifth-Wheel
Trailer 3.73 4 627 kg (10,200 lb) 7 575 kg (16,700 lb)
6.2L V8 – Conventional Trailer 3.23 4 082 kg (9,000 lb) 6 804 kg (15,000 lb)
6.2L V8 – Gooseneck/Fifth-Wheel
Trailer 3.23 3 629 kg (8,000 lb) 6 804 kg (15,000 lb)
6.2L V8 – Conventional Trailer 3.42 5 307 kg (11,700 lb) 8 029 kg (17,700 lb)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
316 Driving and Operating 1500/2500/3500 Series Pickups – SAE J2807 Compliant
Vehicle Axle Ratio Maximum Trailer
Weight (c) GCWR (a)
6.2L V8 – Gooseneck/Fifth-Wheel
Trailer 3.42 4 627 kg (10,200 lb) 8 029 kg (17,700 lb)
1500 Series 4WD Crew Cab Short Box (b)
4.3L V6 3.42 3 175 kg (7,000 lb) 5 806 kg (12,800 lb)
5.3L V8 3.08 2 767 kg (6,100 lb) 5 443 kg (12,000 lb)
5.3L V8 3.42 4 128 kg (9,100 lb) 6 804 kg (15,000 lb)
5.3L V8, 8-speed automatic
transmission with Enhanced
Towing Package 3.42 4 853 kg (10,700 lb) 7 575 kg (16,700 lb)
5.3L V8 3.73 4 853 kg (10,700 lb) 7 575 kg (16,700 lb)
6.2L V8 3.23 4 128 kg (9,100 lb) 6 804 kg (15,000 lb)
6.2L V8 3.42 5 307 kg (11,700 lb) 8 029 kg (17,700 lb)
1500 Series 4WD Regular Cab Long Box
4.3L V6 – Conventional Trailer 3.42 3 357 kg (7,400 lb) 5 806 kg (12,800 lb)
4.3L V6 – Gooseneck/Fifth Wheel 3.42 3 311 kg (7,300 lb) 5 806 kg (12,800 lb)
5.3L V8 – Conventional Trailer 3.08 2 948 kg (6,500 lb) 5 443 kg (12,000 lb)
5.3L V8 – Gooseneck/Fifth Wheel 3.08 2 903 kg (6,400 lb) 5 443 kg (12,000 lb)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Vehicle Care 341
Vehicle Care General Information General Information . . . . . . . . . . 342
California Proposition
65 Warning . . . . . . . . . . . . . . . . . 343
California Perchlorate
Materials Requirements . . . . . 343
Accessories and
Modifications . . . . . . . . . . . . . . . . 343
Vehicle Checks Doing Your Own
Service Work . . . . . . . . . . . . . . . 344
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 344
Engine Compartment
Overview . . . . . . . . . . . . . . . . . . . . 345
Engine Oil . . . . . . . . . . . . . . . . . . . . 350
Engine Oil Life System . . . . . . . 353
Automatic Transmission Fluid
(6-Speed Transmission) . . . . . 354
Automatic Transmission Fluid
(8-Speed Transmission) . . . . . 357
Engine Air Cleaner/Filter . . . . . . 358
Cooling System . . . . . . . . . . . . . . 359
Engine Overheating . . . . . . . . . . 363
Overheated Engine Protection
Operating Mode . . . . . . . . . . . . . 364
Engine Fan . . . . . . . . . . . . . . . . . . . 365 Power Steering Fluid (1500
Series) . . . . . . . . . . . . . . . . . . . . . . 365
Power Steering Fluid (2500/
3500 Series) . . . . . . . . . . . . . . . . 365
Washer Fluid . . . . . . . . . . . . . . . . . 366
Brakes . . . . . . . . . . . . . . . . . . . . . . . 367
Brake Fluid . . . . . . . . . . . . . . . . . . . 368
Battery - North America . . . . . . 369
Four-Wheel Drive . . . . . . . . . . . . . 370
Front Axle . . . . . . . . . . . . . . . . . . . . 370
Rear Axle . . . . . . . . . . . . . . . . . . . . 371
Noise Control System . . . . . . . . 373
Starter Switch Check . . . . . . . . . 374
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 374
Ignition Transmission Lock
Check . . . . . . . . . . . . . . . . . . . . . . . 374
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . 375
Wiper Blade Replacement . . . . 375
Windshield Replacement . . . . . 376
Gas Strut(s) . . . . . . . . . . . . . . . . . . 376
Headlamp Aiming Headlamp Aiming . . . . . . . . . . . . 377
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 378
Halogen Bulbs . . . . . . . . . . . . . . . . 378 High Intensity Discharge (HID)
Lighting . . . . . . . . . . . . . . . . . . . . . 378
LED Lighting . . . . . . . . . . . . . . . . . 378
Taillamps, Turn Signal,
Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 378
Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . . . 380
Electrical System High Voltage Devices and
Wiring . . . . . . . . . . . . . . . . . . . . . . . 380
Electrical System Overload . . . 380
Fuses and Circuit Breakers . . . 381
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 381
Instrument Panel Fuse Block
(Right) . . . . . . . . . . . . . . . . . . . . . . 385
Instrument Panel Fuse
Block (Left) . . . . . . . . . . . . . . . . . 386
Wheels and Tires Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 389
All-Season Tires . . . . . . . . . . . . . . 389
Winter Tires . . . . . . . . . . . . . . . . . . 390
Low-Profile Tires . . . . . . . . . . . . . 390
All-Terrain Tires . . . . . . . . . . . . . . . 391
Tire Sidewall Labeling . . . . . . . . 391
Tire Designations . . . . . . . . . . . . . 393