2012 GMC SIERRA 1500 cooling

Black plate (82,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
9-82 Driving and Operating
VehicleAxle Ratio Maximum Trailer Weight GCWR (a)
5.3L V8 (LMG) K5L HD
Cooling Pkg 3.08
3 130 kg (6,900 lbs) 5 534 kg (12,200 lbs)
5.3L V8 (LC9) XFE 3.083 175 kg (7,000 lbs) 5 534 kg (12,200 lbs)
5.3L V8 (LMG) K5L HD
Cooling Pkg 3.42
4 355 kg (9,600 lbs) 6 804 kg (15,000 lbs)
6.2L V8 K5L HD Cooling Pkg 3.424 400 kg (9,700 lbs) 6 804 kg (15,000 lbs)
6.2L V8 NHT Max Trailering Pkg 3.734 808 kg (10,600 lbs) 7 257 kg (16,000 lbs)
1500 Series 2WD Regular Cab Long Box 4.3L V6 (b) 3.232 132 kg (4,700 lbs) 4 309 kg (9,500 lbs)
4.3L V6 (b) 3.732 359 kg (5,200 lbs) 4 536 kg (10,000 lbs)
4.8L V8 (b) 3.232 313 kg (5,100 lbs) 4 536 kg (10,000 lbs)
4.8L V8 (b) 3.733 221 kg (7,100 lbs) 5 443 kg (12,000 lbs)
5.3L V8 3.082 948 kg (6,500 lbs) 5 216 kg (11,500 lbs)
5.3L V8 K5L HD Cooling Pkg 3.083 266 kg (7,200 lbs) 5 534 kg (12,200 lbs)
5.3L V8 K5L HD Cooling
Pkg —Conventional Trailer 3.42
4 536 kg (10,000 lbs) 6 804 kg (15,000 lbs)
5.3L V8 K5L HD Cooling
Pkg —Fifth-Wheel Trailer 3.42
4 037 kg (8,900 lbs) 6 804 kg (15,000 lbs)

Black plate (83,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Driving and Operating 9-83
VehicleAxle Ratio Maximum Trailer Weight GCWR (a)
1500 Series 2WD Extended Cab Long Box 5.3L V8 (b) 3.082 722 kg (6,000 lbs) 5 216 kg (11,500 lbs)
5.3L V8 K5L HD Cooling Pkg (b) 3.083 039 kg (6,700 lbs) 5 534 kg (12,200 lbs)
5.3L V8 K5L HD Cooling
Pkg —Conventional Trailer 3.42
4 309 kg (9,500 lbs) 6 804 kg (15,000 lbs)
5.3L V8 K5L HD Cooling
Pkg —Fifth-Wheel Trailer 3.42
4 082 kg (9,000 lbs) 6 804 kg (15,000 lbs)
1500 Series 4WD Regular Cab Standard Box 4.3L V6 (b) 3.732 313 kg (5,100 lbs) 4 536 kg (10,000 lbs)
4.8L V8 (b) 3.422 722 kg (6,000 lbs) 4 990 kg (11,000 lbs)
5.3L V8 (b) 3.082 903 kg (6,400 lbs) 5 216 kg (11,500 lbs)
5.3L V8 K5L HD Cooling Pkg 3.083 221 kg (7,100 lbs) 5 534 kg (12,200 lbs)
5.3L V8 K5L HD Cooling
Pkg —Conventional Trailer 3.42
4 037 kg (8,900 lbs) 6 350 kg (14,000 lbs)
5.3L V8 K5L HD Cooling
Pkg —Fifth-Wheel Trailer 3.42
3 719 kg (8,200 lbs) 6 350 kg (14,000 lbs)

Black plate (84,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
9-84 Driving and Operating
VehicleAxle Ratio Maximum Trailer Weight GCWR (a)
1500 Series 4WD Extended Cab Standard Box 4.8L V8 (b) 3.422 495 kg (5,500 lbs) 4 990 kg (11,000 lbs)
5.3L V8 (b) 3.082 767 kg (6,100 lbs) 5 216 kg (11,500 lbs)
5.3L V8 K5L HD Cooling Pkg (b) 3.083 084 kg (6,800 lbs) 5 534 kg (12,200 lbs)
5.3L V8 K5L HD Cooling
Pkg —Conventional Trailer 3.42
4 354 kg (9,600 lbs) 6 804 kg (15,000 lbs)
5.3L V8 K5L HD Cooling
Pkg —Fifth-Wheel Trailer 3.42
4 354 kg (9,600 lbs) 6 804 kg (15,000 lbs)
6.2L V8 K5L HD Cooling
Pkg —Conventional Trailer 3.42
4 264 kg (9,400 lbs) 6 804 kg (15,000 lbs)
6.2L V8 K5L HD Cooling
Pkg —Fifth-Wheel Trailer 3.42
4 128 kg (9,100 lbs) 6 804 kg (15,000 lbs)
6.2L V8 NHT Max Trailering
Pkg —Conventional Trailer 3.73
4 717 kg (10,400 lbs) 7 257 kg (16,000 lbs)
6.2L V8 NHT Max Trailering
Pkg —Fifth-Wheel Trailer 3.73
4 672 kg (10,300 lbs) 7 257 kg (16,000 lbs)
1500 Series 4WD Crew Cab Short Box (b) 4.8L V8 3.422 495 kg (5,500 lbs) 4 990 kg (11,000 lbs)
5.3L V8 3.082 722 kg (6,000 lbs) 5 216 kg (11,500 lbs)

Black plate (85,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Driving and Operating 9-85
VehicleAxle Ratio Maximum Trailer Weight GCWR (a)
5.3L V8 K5L HD Cooling Pkg 3.083 039 kg (6,700 lbs) 5 534 kg (12,200 lbs)
5.3L V8 K5L HD Cooling Pkg 3.424 309 kg (9,500 lbs) 6 804 kg (15,000 lbs)
6.2L V8 K5L HD Cooling Pkg 3.424 264 kg (9,400 lbs) 6 804 kg (15,000 lbs)
6.2L V8 NHT Max Trailering Pkg 3.734 717 kg (10,400 lbs) 7 257 kg (16,000 lbs)
1500 Series 4WD Regular Cab Long Box
4.3L V6 (b) 3.732 223 kg (4,900 lbs) 4 536 kg (10,000 lbs)
4.8L V8 (b) 3.422 631 kg (5,800 lbs) 4 990 kg (11,000 lbs)
5.3L V8 (b) 3.082 858 kg (6,300 lbs) 5 216 kg (11,500 lbs)
5.3L V8 K5L HD Cooling Pkg 3.083 175 kg (7,000 lbs) 5 534 kg (12,200 lbs)
5.3L V8 K5L HD Cooling
Pkg —Conventional Trailer 3.42
4 445 kg (9,800 lbs) 6 804 kg (15,000 lbs)
5.3L V8 K5L HD Cooling
Pkg —Fifth-Wheel Trailer 3.42
4 400 kg (9,700 lbs) 6 804 kg (15,000 lbs)
1500 Series 4WD Extended Cab Long Box 5.3L V8 (b) 3.082 631 kg (5,800 lbs) 5 216 kg (11,500 lbs)
5.3L V8 K5L HD Cooling Pkg (b) 3.082 948 kg (6,500 lbs) 5 534 kg (12,200 lbs)

Black plate (86,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
9-86 Driving and Operating
VehicleAxle Ratio Maximum Trailer Weight GCWR (a)
5.3L V8 K5L HD Cooling
Pkg —Conventional Trailer 3.42
4 218 kg (9,300 lbs) 6 804 kg (15,000 lbs)
5.3L V8 K5L HD Cooling
Pkg —Fifth-Wheel Trailer 3.42
3 674 kg (8,100 lbs) 6 804 kg (15,000 lbs)
2500 Series 2WD Extended Cab Standard Box HD 6.0L V8 3.734 445 kg (9,800 lbs) 7 257 kg (16,000 lbs)
6.0L V8 —Conventional Trailer 4.105 897 kg (13,000 lbs) 9 299 kg (20,500 lbs)
6.0L V8 —Fifth-Wheel Trailer 4.106 486 kg (14,300 lbs) 9 299 kg (20,500 lbs)
2500 Series 2WD Crew Cab Standard Box HD
6.0L V8 3.734 400 kg (9,700 lbs) 7 257 kg (16,000 lbs)
6.0L V8 —Conventional Trailer 4.105 897 kg (13,000 lbs) 9 299 kg (20,500 lbs)
6.0L V8 —Fifth-Wheel Trailer 4.106 441 kg (14,200 lbs) 9 299 kg (20,500 lbs)
2500 Series 2WD Regular Cab Long Box HD
6.0L V8 3.734 627 kg (10,200 lbs) 7 257 kg (16,000 lbs)
6.0L V8 —Payload Performance
Pkg (UB7) 3.73
4 536 kg (10,000 lbs) 7 257 kg (16,000 lbs)
6.0L V8 —Conventional Trailer 4.105 897 kg (13,000 lbs) 9 299 kg (20,500 lbs)
6.0L V8 —Fifth-Wheel Trailer 4.106 668 kg (14,700 lbs) 9 299 kg (20,500 lbs)

Black plate (1,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Vehicle Care 10-1
Vehicle Care
General Information
General Information . . . . . . . . . . 10-2
California Proposition65 Warning . . . . . . . . . . . . . . . . . 10-3
California Perchlorate Materials Requirements . . . . 10-3
Accessories and Modifications . . . . . . . . . . . . . . . 10-3
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 10-4
Hood . . . . . . . . . . . . . . . . . . . . . . . . 10-5
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . 10-6
Engine Oil . . . . . . . . . . . . . . . . . . . 10-7
Engine Oil Life System . . . . . 10-10
Automatic Transmission Fluid (4-Speed Transmission) . . . 10-11
Automatic Transmission Fluid (6-Speed
Transmission) . . . . . . . . . . . . . 10-14
Engine Air Cleaner/Filter . . . . 10-17
Cooling System . . . . . . . . . . . . 10-18
Engine Coolant . . . . . . . . . . . . . 10-19
Engine Overheating . . . . . . . . 10-22 Overheated Engine
Protection
Operating Mode . . . . . . . . . . . 10-24
Engine Fan . . . . . . . . . . . . . . . . . 10-24
Power Steering Fluid . . . . . . . 10-25
Washer Fluid . . . . . . . . . . . . . . . 10-26
Brakes . . . . . . . . . . . . . . . . . . . . . 10-27
Brake Fluid . . . . . . . . . . . . . . . . . 10-28
Battery . . . . . . . . . . . . . . . . . . . . . 10-30
Four-Wheel Drive . . . . . . . . . . . 10-30
Front Axle . . . . . . . . . . . . . . . . . . 10-31
Rear Axle . . . . . . . . . . . . . . . . . . 10-32
Noise Control System . . . . . . 10-34
Starter Switch Check . . . . . . . 10-35
Automatic Transmission Shift Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . 10-35
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . 10-35
Park Brake and P (Park) Mechanism Check . . . . . . . . 10-36
Wiper Blade Replacement . . . . . . . . . . . . . . 10-36
Glass Replacement . . . . . . . . 10-37
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . 10-37
Bulb Replacement
Bulb Replacement . . . . . . . . . . 10-39
Halogen Bulbs . . . . . . . . . . . . . . 10-39
Headlamps, Front Turn Signal, Sidemarker, and
Parking Lamps . . . . . . . . . . . . 10-39
Pick-Up Box Identification and Fender Marker
Lamps . . . . . . . . . . . . . . . . . . . . 10-40
Taillamps (Chassis Cab Models) . . . . . . . . . . . . . . . . . . . 10-40
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . 10-41
Center High-Mounted Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . 10-42
License Plate Lamp . . . . . . . . 10-42
Replacement Bulbs . . . . . . . . . 10-43
Electrical System
Electrical System Overload . . . . . . . . . . . . . . . . . . 10-43
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . 10-44
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . 10-44
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . 10-48

Black plate (7,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Vehicle Care 10-7
A.Engine Air Cleaner/Filter on
page 10‑17.
B. Coolant Surge Tank and Pressure Cap. See Cooling
System on page 10‑18.
C. Positive (+) Terminal. See Jump
Starting on page 10‑88.
D. Battery on page 10‑30.
E. Remote Negative (−) Terminal (Out of View). See Jump
Starting on page 10‑88.
F. Automatic Transmission Dipstick (Out of View). See
“Checking the Fluid Level”
under Automatic Transmission
Fluid (4-Speed Transmission)
on page 10‑11 orAutomatic
Transmission Fluid (6-Speed
Transmission) on page 10‑14.
G. Engine Oil Fill Cap. See “When
to Add Engine Oil” under
Engine Oil on page 10‑7. H. Engine Oil Dipstick (Out of
View). See “Checking Engine
Oil” under Engine Oil on
page 10‑7.
I. Engine Cooling Fan (Out of View). See Cooling System on
page 10‑18.
J. Power Steering Fluid Reservoir. See Power Steering Fluid on
page 10‑25.
K. Brake Master Cylinder Reservoir. See Brake Fluid on
page 10‑28.
L. Engine Compartment Fuse
Block on page 10‑44.
M. Windshield Washer Fluid Reservoir. See “Adding Washer
Fluid” under Washer Fluid on
page 10‑26.
If the vehicle has a diesel engine
and/or an Allison Transmission, see
the Duramax Diesel Supplement.Engine Oil
For diesel engine vehicles, see
“Engine Oil” in the Duramax Diesel
Supplement.
To ensure proper engine
performance and long life, careful
attention must be paid to engine
oil. Following these simple, but
important steps will help protect
your investment:
.Always use engine oil approved
to the proper specification and of
the proper viscosity grade. See
“Selecting the Right Engine Oil”
in this section.
.Check the engine oil level
regularly and maintain the
proper oil level. See “Checking
Engine Oil” and“When to Add
Engine Oil” in this section.
.Change the engine oil at the
appropriate time. See Engine Oil
Life System on page 10‑10.
.Always dispose of engine oil
properly. See “What to Do with
Used Oil” in this section.

Black plate (18,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
10-18 Vehicle Care
3. Remove the engine air cleaner/filter from the housing. Take
care to dislodge as little dirt as
possible.
4. Clean the engine air cleaner/ filter sealing surfaces and the
housing.
5. Inspect or replace the engine air cleaner/filter.
6. Reinstall the cover and tighten the screws.
{WARNING
Operating the engine with the air
cleaner/filter off can cause you
or others to be burned. The air
cleaner not only cleans the air; it
helps to stop flames if the engine
backfires. Use caution when
working on the engine and do not
drive with the air cleaner/filter off.
Cooling System
If the vehicle has the Duramax®
Diesel engine, see the Duramax®
Diesel Supplement for more
information.
The cooling system allows the
engine to maintain the correct
working temperature.
5.3 L Engine Shown (4.3 L, 4.8 L,
6.0 L and, 6.2 L Engines Similar)
A. Coolant Surge Tank
B. Coolant Surge Tank Pressure Cap
C. Engine Cooling Fan (Out of View)
{WARNING
An electric engine cooling fan
can start even when the engine
is not running. To avoid injury,
always keep hands, clothing,
and tools away from any engine
cooling fan.