A Tire and Loading Information label is attached tothe vehicle’s center pillar. This label lists yourvehicle’s original equipment tires and shows thecorrect inflation pressures for your tires when theyare cold. The recommended cold tire inflationpressure, shown on the label, is the minimumamount of air pressure needed to supportyour vehicle’s maximum load carrying capacity.
For additional information regarding how muchweight your vehicle can carry, and an example ofthe Tire and Loading Information label, seeLoading the Vehicle on page 5-18. How you loadyour vehicle affects the vehicle handling andride comfort, never load your vehicle with moreweight than it was designed to carry.
When to Check
Check your tires once a month or more. Do notforget to check the spare tire. If your vehicle has acompact spare tire, it should be at 60 psi (420 kPa).For additional information seeSpare Tire onpage 6-90.
How to Check
Use a good quality pocket-type gage to check tirepressure. You cannot tell if your tires areproperly inflated simply by looking at them. Radialtires may look properly inflated even when theyare under-inflated. Check the tire’s inflationpressure when the tires are cold. Cold means yourvehicle has been sitting for at least three hoursor driven no more than 1 mile (1.6 km).
Remove the valve cap from the tire valve stem.Press the tire gage firmly onto the valve toget a pressure measurement. If the cold tireinflation pressure matches the recommendedpressure on the Tire and Loading Informationlabel, no further adjustment is necessary. If theinflation pressure is low, add air until you reach therecommended amount.
If you overfill the tire, release air by pushing onthe metal stem in the center of the tire valve.Re-check the tire pressure with the tire gage.
Be sure to put the valve caps back on the valvestems. They help prevent leaks by keeping out dirtand moisture.
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Professional Vehicle
The proper inflation of the tires on yourprofessional vehicle depends on the type of tireson it.
•If your vehicle has P235/60R17 size tires, the
cold inflation pressure is 41 psi (284 kPa).
•If your vehicle has LT235/60R17E size tires,
the cold inflation pressure depends on thevehicle mass and should be determined by thevehicle coach-builder. A Tire and LoadingInformation label provided by the final stagemanufacturer should be attached to the B-pillaron the driver’s side of the vehicle. If the finalstage manufacturer’s label is not present,the coach-builder should be consulted. Do notuse the tire pressures indicated on theGeneral Motors label. These tire pressures arefor the incomplete vehicle and are not thecorrect tire pressures for the completedprofessional vehicle.
Operation at inflation pressures below thisrecommendation may cause your tires to becomeoverloaded.
High-Speed Operation
{WARNING:
Driving at high speeds, 160 km/h (100 mph) or
higher, puts an additional strain on tires. Sustained
high-speed driving causes excessive heat build up
and can cause sudden tire failure. You could have
a crash and you or others could be killed. Some
high-speed rated tires require inflation pressure
adjustment for high speed operation. When speed
limits and road conditions are such that a vehicle
can be driven at high speeds, make sure the tires
are rated for high speed operation, in excellent
condition, and set to the correct cold tire inflation
pressure for the vehicle load.
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A five-tire rotation pattern may be used for yourprofessional vehicle, if it has a full-size sparetire and wheel assembly that matches the originalequipment tires and wheels in size, type andbrand. The correct five-tire rotation patternis shown.
After the tires have been rotated, adjust the frontand rear inflation pressures as shown on theTire and Loading Information label. SeeLoadingthe Vehicle on page 5-18.
Vehicles that have the Tire Pressure MonitorSystem (TPMS) will need to have the sensorsreset after a tire rotation is performed. SeeTire Pressure Monitor System on page 6-57.
Make certain that all wheel nuts are properlytightened. See “Wheel Nut Torque” underCapacities and Specifications on page 6-109.
{WARNING:
Rust or dirt on a wheel, or on the parts towhich it is fastened, can make wheel nutsbecome loose after time. The wheel couldcome off and cause an accident. When youchange a wheel, remove any rust or dirt fromplaces where the wheel attaches to thevehicle. In an emergency, you can use acloth or a paper towel to do this; but be sureto use a scraper or wire brush later, ifneeded, to get all the rust or dirt off. SeeChanging a Flat Tire on page 6-80.
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GM’s exclusive TPC Spec system considers over adozen critical specifications that impact the overallperformance of your vehicle, including brake systemperformance, ride and handling, traction control, and tirepressure monitoring performance. GM’s TPC Specnumber is molded onto the tire’s sidewall near the tiresize. If the tires have an all-season tread design,the TPC Spec number will be followed by an MS formud and snow. SeeTire Sidewall Labeling on page 6-47for additional information.
GM recommends replacing tires in sets of four. This isbecause uniform tread depth on all tires will helpkeep your vehicle performing most like it did when thetires were new. Replacing less than a full set of tires canaffect the braking and handling performance of yourvehicle. SeeTire Inspection and Rotation on page 6-62for information on proper tire rotation.
{WARNING:
Mixing tires could cause you to lose control of
your vehicle while driving. If you mix tires of
different sizes, brands, or types (radial and
bias-belted tires), the vehicle may not handle
properly, and you could have a crash. Using tires
of different sizes, brands, or types may also cause
damage to your vehicle. Be sure to use the correct
size, brand, and type of tires on all wheels.
Your vehicle may have a compact spare tire and
wheel assembly. If the vehicle has a compact
spare tire and wheel, they have the same overall
diameter as your vehicle’s full-size tires and
wheels. Because they were designed and
developed for use on your vehicle, it is all right to
drive your vehicle with the compact spare installed
properly. Compact spare tires are designed for
temporary use only. SeeSpare Tire on page 6-90.
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{WARNING:
If you use bias-ply tires on the vehicle, thewheel rim flanges could develop cracks aftermany miles of driving. A tire and/or wheelcould fail suddenly, causing a crash. Useonly radial-ply tires with the wheels onthe vehicle.
If you must replace your vehicle’s tires with those thatdo not have a TPC Spec number, make sure theyare the same size, load range, speed rating, andconstruction type (radial and bias-belted tires) as yourvehicle’s original tires.
Vehicles that have a tire pressure monitoring systemcould give an inaccurate low-pressure warning ifnon-TPC Spec rated tires are installed on your vehicle.Non-TPC Spec rated tires may give a low-pressurewarning that is higher or lower than the proper warninglevel you would get with TPC Spec rated tires. SeeTire Pressure Monitor System on page 6-57.
Your vehicle’s original equipment tires are listed on theTire and Loading Information Label. SeeLoadingthe Vehicle on page 5-18, for more information aboutthe Tire and Loading Information Label and its locationon your vehicle.
Different Size Tires and Wheels
If you add wheels or tires that are a different size thanyour original equipment wheels and tires, this mayaffect the way your vehicle performs, including itsbraking, ride and handling characteristics, stability, andresistance to rollover. Additionally, if your vehiclehas electronic systems such as, antilock brakes, tractioncontrol, and electronic stability control, the performanceof these systems can be affected.
{WARNING:
If you add different sized wheels, your vehicle may
not provide an acceptable level of performance
and safety if tires not recommended for those
wheels are selected. You may increase the
chance that you will crash and suffer serious
injury. Only use GM specific wheel and tire
systems developed for your vehicle, and have
them properly installed by a GM certified
technician.
SeeBuying New Tires on page 6-64andAccessoriesand Modifications on page 6-3for additional information.
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Uniform Tire Quality Grading
Quality grades can be found where applicable onthe tire sidewall between tread shoulder andmaximum section width. For example:
Treadwear 200 Traction AA
Temperature A
The following information relates to the systemdeveloped by the United States National HighwayTraffic Safety Administration (NHTSA), whichgrades tires by treadwear, traction, andtemperature performance. This applies only tovehicles sold in the United States. The grades aremolded on the sidewalls of most passenger cartires. The Uniform Tire Quality Grading (UTQG)system does not apply to deep tread, winter-typesnow tires, space-saver, or temporary usespare tires, tires with nominal rim diameters of10 to 12 inches (25 to 30 cm), or to somelimited-production tires.
While the tires available on General Motorspassenger cars and light trucks may vary withrespect to these grades, they must also conformto federal safety requirements and additionalGeneral Motors Tire Performance Criteria (TPC)standards.
Treadwear
The treadwear grade is a comparative ratingbased on the wear rate of the tire when testedunder controlled conditions on a specifiedgovernment test course. For example, a tiregraded 150 would wear one and a half (1.5) timesas well on the government course as a tiregraded 100. The relative performance of tiresdepends upon the actual conditions of their use,however, and may depart significantly fromthe norm due to variations in driving habits, servicepractices, and differences in road characteristicsand climate.
Traction – AA, A, B, C
The traction grades, from highest to lowest, areAA, A, B, and C. Those grades represent the tire’sability to stop on wet pavement as measuredunder controlled conditions on specifiedgovernment test surfaces of asphalt and concrete.A tire marked C may have poor tractionperformance.
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Tire Chains
{WARNING:
Do not use tire chains. There is not enough
clearance. Tire chains used on a vehicle without
the proper amount of clearance can cause
damage to the brakes, suspension or other vehicle
parts. The area damaged by the tire chains could
cause you to lose control of the vehicle and you or
others may be injured in a crash.
Use another type of traction device only if its
manufacturer recommends it for use on the
vehicle and tire size combination and road
conditions. Follow that manufacturer’s instructions.
To help avoid damage to the vehicle, drive slowly,
readjust or remove the device if it is contacting the
vehicle, and do not spin the vehicle’s wheels. If
you do find traction devices that will fit, install
them on the front tires.
If a Tire Goes Flat
It is unusual for a tire to blowout while you are driving,especially if you maintain your vehicle’s tires properly.If air goes out of a tire, it is much more likely to leak outslowly. But if you should ever have a blowout, hereare a few tips about what to expect and what to do:
If a front tire fails, the flat tire creates a drag that pullsthe vehicle toward that side. Take your foot off theaccelerator pedal and grip the steering wheel firmly.Steer to maintain lane position, and then gently brake toa stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like askid and may require the same correction you woulduse in a skid. In any rear blowout remove your foot fromthe accelerator pedal. Get the vehicle under controlby steering the way you want the vehicle to go. It maybe very bumpy and noisy, but you can still steer. Gentlybrake to a stop, well off the road if possible.
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Spare Tire
This vehicle may have a spare tire, which, when new,was fully inflated. A spare tire may lose air over time, socheck its inflation pressure regularly. SeeInflation - TirePressure on page 6-54andLoading the Vehicle onpage 5-18for information regarding proper tire inflationand loading your vehicle. For instructions on how toremove, install or store a spare tire, seeRemoving theFlat Tire and Installing the Spare Tire on page 6-83.
After installing the spare tire on your vehicle, you shouldstop as soon as possible and make sure the spare iscorrectly inflated. Have the damaged or flat roadtire repaired or replaced as soon as you can andinstalled back onto your vehicle. This way, a spare tirewill be available in case you need it again.
Your vehicle may have a different size spare tire thanthe road tire originally installed on your vehicle.This spare tire was developed for use on your vehicle,so it is all right to drive on it.
If your vehicle has a spare tire that does not match yourvehicle’s original road tires and wheels in size andtype, do not include the spare in the tire rotation.
Appearance Care
Interior Cleaning
The vehicle’s interior will continue to look its best if it iscleaned often. Although not always visible, dust anddirt can accumulate on the upholstery. Dirt can damagecarpet, fabric, leather, and plastic surfaces. Regularvacuuming is recommended to remove particles from theupholstery. It is important to keep the upholstery frombecoming and remaining heavily soiled. Soils should beremoved as quickly as possible. The vehicle’s interiormay experience extremes of heat that could causestains to set rapidly.
Lighter colored interiors may require more frequentcleaning. Use care because newspapers and garmentsthat transfer color to home furnishings may alsotransfer color to the vehicle’s interior.
When cleaning the vehicle’s interior, only use cleanersspecifically designed for the surfaces being cleaned.Permanent damage may result from using cleaners onsurfaces for which they were not intended. Use glasscleaner only on glass. Remove any accidental over-sprayfrom other surfaces immediately. To prevent over-spray,apply cleaner directly to the cleaning cloth.
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