tire pressure GMC SIERRA CLASSIC 2007 Owners Manual

Let us say the road is wet and you are driving
safely. Suddenly, an animal jumps out in front of
you. You slam on the brakes and continue braking.
Here is what happens with ABS:
A computer senses that wheels are slowing down.
If one of the wheels is about to stop rolling, the
computer will separately work the brakes at each
front wheel and at both rear wheels.ABS can change the brake pressure faster than
any driver could. The computer is programmed
to make the most of available tire and road
conditions. This can help you steer around the
obstacle while braking hard.
As you brake, your computer keeps receiving
updates on wheel speed and controls braking
pressure accordingly.
362

Hydroplaning
Hydroplaning is dangerous. So much water can
build up under your tires that they can actually ride
on the water. This can happen if the road is wet
enough and you are going fast enough. When your
vehicle is hydroplaning, it has little or no contact
with the road.
Hydroplaning does not happen often. But it can
if your tires do not have much tread or if the
pressure in one or more is low. It can happen if a
lot of water is standing on the road. If you can
see reections from trees, telephone poles,
or other vehicles, and raindrops dimple the water’s
surface, there could be hydroplaning.
Hydroplaning usually happens at higher speeds.
There just is not a hard and fast rule about
hydroplaning. The best advice is to slow down
when it is raining.
Driving Through Deep Standing Water
Notice:If you drive too quickly through
deep puddles or standing water, water can
come in through your engine’s air intake and
badly damage your engine. Never drive through
water that is slightly lower than the underbody
of your vehicle. If you cannot avoid deep
puddles or standing water, drive through them
very slowly.
394

Here are some things you can check before a trip:
Windshield Washer Fluid:Is the reservoir
full? Are all windows clean inside and outside?
Wiper Blades:Are they in good shape?
Fuel, Engine Oil, Other Fluids:Have you
checked all levels?
Lamps:Are they all working? Are the lenses
clean?
Tires:They are vitally important to a safe,
trouble-free trip. Is the tread good enough
for long-distance driving? Are the tires
all inated to the recommended pressure?
Weather Forecasts:What is the weather
outlook along your route? Should you
delay your trip a short time to avoid a major
storm system?
Maps:Do you have up-to-date maps?
Highway Hypnosis
Is there actually such a condition as highway
hypnosis? Or is it just plain falling asleep at the
wheel? Call it highway hypnosis, lack of
awareness, or whatever.
There is something about an easy stretch of road
with the same scenery, along with the hum of the
tires on the road, the drone of the engine, and the
rush of the wind against the vehicle that can make
you sleepy. Do not let it happen to you! If it does,
your vehicle can leave the road in less than a
second, and you could crash and be injured.
What can you do about highway hypnosis?
First, be aware that it can happen.
Then here are some tips:
Make sure your vehicle is well ventilated,
with a comfortably cool interior.
Keep your eyes moving. Scan the road ahead
and to the sides. Check your mirrors and your
instruments frequently.
If you get sleepy, pull off the road into a rest,
service, or parking area and take a nap, get
some exercise, or both. For safety, treat
drowsiness on the highway as an emergency.
399

The Tire and Loading Information label also shows
the size of the original equipment tires (C) and
the recommended cold tire ination pressures (D).
For more information on tires and ination see
Tires on page 543andInation - Tire Pressure on
page 551.
There is also important loading information on the
vehicle Certication/Tire label. It tells you the
Gross Vehicle Weight Rating (GVWR) and
the Gross Axle Weight Rating (GAWR) for the
front and rear axles. See “Certication/Tire Label”
later in this section.
Steps for Determining Correct Load Limit
1. Locate the statement “The combined
weight of occupants and cargo should never
exceed XXX kg or XXX lbs” on your
vehicle’s placard.
2. Determine the combined weight of the driver
and passengers that will be riding in your
vehicle.
3. Subtract the combined weight of the driver
and passengers from XXX kg or XXX lbs.4. The resulting gure equals the available
amount of cargo and luggage load capacity.
For example, if the “XXX” amount equals
1400 lbs and there will be ve 150 lb
passengers in your vehicle, the amount of
available cargo and luggage load capacity is
650 lbs (1400−750 (5 x 150) = 650 lbs).
5. Determine the combined weight of luggage
and cargo being loaded on the vehicle.
That weight may not safely exceed the
available cargo and luggage load capacity
calculated in Step 4.
6. If your vehicle will be towing a trailer, the load
from your trailer will be transferred to your
vehicle. Consult this manual to determine how
this reduces the available cargo and luggage
load capacity of your vehicle. SeeTowing
a Trailer on page 429for important information
on towing a trailer, towing safety rules and
trailering tips.
410

Item Description Total
AVehicle Capacity Weight
for Example 3=1,000 lbs (453 kg)
BSubtract Occupant
Weight 200 lbs
(91 kg)×5=1000 lbs (453 kg)
CAvailable Cargo Weight
=0 lbs (0 kg)
Refer to your vehicle’s tire and loading
information label for specic information about
your vehicle’s capacity weight and seating
positions. The combined weight of the driver,
passengers, and cargo should never exceed your
vehicle’s capacity weight.
Certication/Tire Label
A vehicle specic Certication/Tire label is found
on the rear edge of the driver’s door. The label
shows the size of your vehicle’s original tires and
the ination pressures needed to obtain the
gross weight capacity of your vehicle. This is
called Gross Vehicle Weight Rating (GVWR).
The GVWR includes the weight of the vehicle,
all occupants, fuel, and cargo.
The Certication/Tire label also tells you the
maximum weights for the front and rear axles,
called Gross Axle Weight Rating (GAWR).
Example 3
412

Noise Control System................................. 531
Tampering with Noise Control System
Prohibited.............................................. 531
Bulb Replacement....................................... 532
Halogen Bulbs........................................... 532
Headlamps................................................ 533
Front Turn Signal, Sidemarker and
Daytime Running Lamps........................ 534
Roof Marker Lamps................................... 535
Center High-Mounted Stoplamp (CHMSL)
and Cargo Lamp.................................... 537
Pickup Box Identication and Fender
Marker Lamps........................................ 538
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps...................................... 539
License Plate Lamp................................... 541
Replacement Bulbs................................... 541
Windshield Wiper Blade Replacement....... 542
Tires............................................................ 543
Tire Sidewall Labeling............................... 544
Tire Terminology and Denitions............... 548
Ination - Tire Pressure............................. 551
Dual Tire Operation................................... 552Tire Inspection and Rotation...................... 553
When It Is Time for New Tires.................. 555
Buying New Tires...................................... 556
Different Size Tires and Wheels................ 558
Uniform Tire Quality Grading..................... 559
Wheel Alignment and Tire Balance............ 560
Wheel Replacement.................................. 560
Tire Chains............................................... 562
If a Tire Goes Flat.................................... 563
Changing a Flat Tire................................. 564
Removing the Spare Tire and Tools.......... 566
Removing the Flat Tire and Installing
the Spare Tire....................................... 571
Secondary Latch System........................... 580
Storing a Flat or Spare Tire and Tools...... 584
Spare Tire................................................. 588
Appearance Care........................................ 589
Cleaning the Inside of Your Vehicle.......... 589
Fabric/Carpet............................................. 590
Leather...................................................... 591
Instrument Panel, Vinyl, and Other
Plastic Surfaces..................................... 591
Care of Safety Belts.................................. 592
Weatherstrips............................................ 592
Section 5 Service and Appearance Care
466

Tires
Your new vehicle comes with high-quality tires
made by a leading tire manufacturer. If you ever
have questions about your tire warranty and where
to obtain service, see your GM Warranty booklet
for details. For additional information refer to
the tire manufacturer’s booklet included with your
vehicle.
{CAUTION:
Poorly maintained and improperly used
tires are dangerous.
Overloading your vehicle’s tires can
cause overheating as a result of too
much friction. You could have an
air-out and a serious accident. See
Loading Your Vehicle on page 409.
CAUTION: (Continued)
CAUTION: (Continued)

Underinated tires pose the
samedanger as overloaded tires. The
resulting accident could cause serious
injury. Check all tires frequently to
maintain the recommended pressure.
Tire pressure should be checked when
your vehicle’s tires are cold. See
Inflation - Tire Pressure on page 551.
Overinated tires are more likely
to be cut, punctured, or broken by a
sudden impact — such as when
you hit a pothole. Keep tires at the
recommended pressure.
Worn, old tires can cause accidents.
If the tire’s tread is badly worn, or
if your vehicle’s tires have been
damaged, replace them.
543

(B) TPC Spec (Tire Performance Criteria
Specication):Original equipment tires designed
to GM’s specic tire performance criteria have
a TPC specication code molded onto the sidewall.
GM’s TPC specications meet or exceed all
federal safety guidelines.
(C) DOT (Department of Transportation):The
Department of Transportation (DOT) code
indicates that the tire is in compliance with the
U.S. Department of Transportation Motor Vehicle
Safety Standards.
(D) Tire Identication Number (TIN):The letters
and numbers following DOT code are the Tire
Identication Number (TIN). The TIN shows
the manufacturer and plant code, tire size, and
date the tire was manufactured. The TIN is
molded onto both sides of the tire, although only
one side may have the date of manufacture.(E) Tire Ply Material:The type of cord and
number of plies in the sidewall and under
the tread.
(F) Uniform Tire Quality Grading (UTQG):Tire
manufacturers are required to grade tires
based on three performance factors: treadwear,
traction, and temperature resistance. For more
information, seeUniform Tire Quality Grading on
page 559.
(G) Maximum Cold Ination Load
Limit:Maximum load that can be carried and the
maximum pressure needed to support that load.
For information on recommended tire pressure see
Ination - Tire Pressure on page 551andLoading
Your Vehicle on page 409.
545

(A) Tire Size:The tire size code is a combination
of letters and numbers used to dene a particular
tire’s width, height, aspect ratio, construction
type, and service description. See the “Tire Size”
illustration later in this section for more detail.(B) TPC Spec (Tire Performance Criteria
Specication):Original equipment tires designed
to GM’s specic tire performance criteria have
a TPC specication code molded onto the sidewall.
GM’s TPC specications meet or exceed all
federal safety guidelines.
(C) Dual Tire Maximum Load:Maximum load
that can be carried and the maximum pressure
needed to support that load when used in a dual
conguration. For information on recommended
tire pressure seeInation - Tire Pressure on
page 551andLoading Your Vehicle on page 409.
(D) DOT (Department of Transportation):The
Department of Transportation (DOT) code
indicates that the tire is in compliance with the
U.S. Department of Transportation Motor Vehicle
Safety Standards.
(E) Tire Identication Number (TIN):The letters
and numbers following DOT code are the Tire
Identication Number (TIN). The TIN shows
the manufacturer and plant code, tire size, and
date the tire was manufactured. The TIN is
molded onto both sides of the tire, although only
one side may have the date of manufacture.
Light Truck (LT-Metric) Tire
546

(F) Tire Ply Material:The type of cord and
number of plies in the sidewall and under
the tread.
(G) Single Tire Maximum Load:Maximum load
that can be carried and the maximum pressure
needed to support that load when used as a
single. For information on recommended
tire pressure seeInation - Tire Pressure on
page 551andLoading Your Vehicle on page 409.
Tire Size
The following examples show the different parts of
a tire size.(A) Passenger (P-Metric) Tire:The United States
version of a metric tire sizing system. The letter P
as the rst character in the tire size means a
passenger vehicle tire engineered to standards set
by the U.S. Tire and Rim Association.
(A) Light Truck (LT-Metric) Tire:The United
States version of a metric tire sizing system. The
letters LT as the rst two characters in the tire
size means a light truck tire engineered to
standards set by the U.S. Tire and Rim
Association.
(B) Tire Width:The three-digit number indicates
the tire section width in millimeters from sidewall
to sidewall.
Passenger (P-Metric) Tire
Light Truck (LT-Metric) Tire
547