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Correct Tire Pressure?

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Old 03-19-2005, 02:02 AM
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Default Correct Tire Pressure?

I recently purchased new rims and tires for my tc and was wondering what the correct tire pressure to inflate them to is. The size is 225/40/18.
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Old 03-19-2005, 02:06 AM
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read the sidewall of the tire....
the info you seek is on the tire. each tire manufacture is diff so it useless to ask...
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Old 03-19-2005, 02:11 AM
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Originally Posted by dgHotLava
read the sidewall of the tire....
the info you seek is on the tire. each tire manufacture is diff so it useless to ask...

Word.
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Old 03-19-2005, 02:23 AM
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Actually , the sidewall of the tires list what the maximum air pressure for the tire is. Usually not the best idea to run them at the maximum, otherwise you will have a very stiff ride, and wear the tires more on the center due to the vehicle not weighing enough to call for that much air pressure. You ideally need to find a chart and match up your load index to what the stock tire air pressure/load index is. IE if the car came with 205/65-R15 89T and your tire is a 225/40-ZR18 94W, you need to use the 89T and the 94W along with the manufacturer recommened air pressure to figure out the right one for your tires.
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Old 03-19-2005, 04:09 PM
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The max inflation is 44psi but I certaintly dont want to inflate them to that. The stock tire size reccomends to inflate them to 32psi cold. Im not sure if I should be a little over 32psi or a little under. Right now they are at 36psi cold. I was hoping that someone with the optional factory 18 inch rims would chime in and tell me what they have theirs inflated to because my tires are the identical size as the factory options.
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Old 03-19-2005, 08:29 PM
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I usually set my tires to ~2psi below max and watch for center wear. Higher pressures = less rolling resistance = better mpg.
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Old 03-20-2005, 02:11 AM
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Also with lower profile tires, a higher tire pressure will give more protection from bending a rim. I run 45 psi (tires rate max 50psi) on my 19s and I dont find them to harsh of a ride.
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Old 03-20-2005, 02:27 AM
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dont forget it varies from cold to hot! and always make it a lil below the max psi. Give some room for expansion when it gets hot.
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Old 03-20-2005, 04:40 AM
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Originally Posted by burn6010
You ideally need to find a chart and match up your load index to what the stock tire air pressure/load index is.
Any idea where one can find such a chart? I'd be very interested in seeing it.
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Old 03-20-2005, 05:41 AM
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I did some quick searching on google earlier to no avail, but we do have them at work...I will see about getting a copy for myself.
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Old 03-20-2005, 01:22 PM
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This pages is based on a booklet that provides an understanding of the many factors essential to proper care and service of automobile and light truck tires. However, the RMA makes no pretense that this booklet is all inclusive. Questions pertaining to specific product should be addressed to the tire dealer or tire manufacturer. Order hard copies of the Tire Care and Safety Guide.



Inflation Pressure


Inspect Your Tires Regularly


Good Driving Habits


Vehicle Conditions Affecting Tires


The Sidewall Story


Replacement Tire Selection


Cold-Weather Driving


Service Assistance


Storage Tips



INFLATION PRESSURE


Tires are designed and built with great care to provide thousands of miles of excellent service. But for maximum benefit they must be maintained properly.


The most important factors in tire care are:


Proper Inflation Pressure

Proper Vehicle Loading

Proper Tire Wear

Regular Inspection

Good Driving Habits

Vehicle Condition




The Benefits of Proper Inflation


With the right amount of air pressure, you will achieve optimum tire performance. This means your tires wear longer, save fuel and help prevent accidents. The "right amount" of air is the pressure specified by the vehicle manufacturer, which may be different on the front than the rear tires on your particular model car or light truck. The correct air pressure is shown on the tire placard (or sticker) attached to the vehicle door edge, door post, glove box door or fuel door. If your vehicle doesn't have a placard, check the owner's manual or consult with the vehicle manufacturer, tire manufacturer or your local tire dealer for the proper inflation.


The tire placard tells you the maximum vehicle load, the cold tire air pressures and the tire size recommended by the vehicle manufacturer.


If you don't take proper care of your tires, the results can be serious. Most tire companies are either supplying a handbook or are molding a safety warning right onto the tire sidewall. A typical warning is shown on this page.


As you see, it points out that serious injury may result from tire failure due to underinflation or overloading. Motorists are strongly advised to follow the vehicle owner's manual or the tire placard in the vehicle for proper inflation and loading.


Only specially trained persons should mount or demount tires. An explosion of a tire and wheel assembly can result from improper or careless mounting procedures.


Persons who do mount tires must have the right equipment, the right training and the right information before proceeding. Never exceed 40 psi to seat the beads. Always use a restraining device when mounting a tire on a rim, and be sure to stay back from the tire when inflating it. Make sure to follow the inflation instructions. Contact the Rubber Manufacturers Association at (202) 682-4800 for proper mounting and demounting information.


Remember, mounting and demounting tires and wheels should be left to skilled professionals who are aware of the safety hazards involved and who have the proper tools and equipment to do the job safely.




WARNING
Serious Injury May Result From:

Tire Failure Due to Underinflation/Overloading
Follow owner's manual or certification label in vehicle.


Explosion of tire/rim assembly due to improper mounting
Only specially trained persons should mount tires.







WARNING

There is a danger of serious injury or death if a tire of one bead diameter is installed on a rim or wheel of a different rim diameter.


Always replace a tire with another tire of exactly the same bead diameter designation and suffix letters.

For example: A 16" tire goes on a 16" rim. Never mount a 16" tire on a 16.5" rim. A 16.5" tire goes on a 16.5" rim. Never mount a 16.5" tire on a 16" rim.

While it is possible to pass a 16" diameter tire over the lip or flanges of a 16.5" size diameter rim, it cannot be inflated enough to position itself against the rim flange. If an attempt is made to seat the tire bead by inflating, the tire bead will break with explosive force and could cause serious injury or death.


Your Own Tire Pressure Gauge


It is difficult to tell just by looking at radial tires whether they are underinflated. It is important that tires be properly inflated. Failure to maintain correct inflation pressures may result in rapid wear and uneven tread wear, improper vehicle handling and excessive heat buildup which may result in tire failure. (Evidence of air loss or repeated underinflation requires tire removal and expert inspection.)


Air pressure enables a tire to support the load, so proper inflation is critical. It is impossible to determine whether tires are properly inflated just by looking at them (see photo). That's why it's important to check your tires using an accurate tire gauge which can be purchased at your tire dealer, auto supply store or other retailer.




Purchase an accurate tire gauge from your tire dealer, auto supply store or other retailer.


Inflation Tips


Check tire inflation pressure (including the spare) at least once a month and before every long trip. Tires must be checked when they are cold; that is, before they have been run a mile. If you must drive over one mile for air, before you leave home, measure the cold inflation pressure of each tire and record the actual under-inflation amount for each tire.


Upon arriving at the service station, measure the inflation pressure of each tire again, then inflate the warm tire(s) to a level equal to the warm pressure plus the underinflated amount you measured when the tire was cold. If the cold tire inflation pressure matches the placard recommendation, then no further adjustment is necessary for the warm tire.


Underinflation


When operating a vehicle equipped with radial tires, it is difficult to notice when a tire has lost air, or is near flat.


Tires lose air normally through the process of permeation. Changes in outdoor temperature can affect the rate in which your tire loses air. This change is more pronounced in hot weather. Generally speaking, a tire may lose one or two pounds of air per month in cool weather, and even more in warmer weather. Underinflation is the leading cause of tire failure, so check inflation pressure regularly.


Never "bleed" or reduce air pressure when tires are hot. It is normal for pressures to build up as a result of driving.


Make sure all tire valves and extensions are equipped with valve caps to keep out dirt and moisture. Have a new valve stem assembly installed whenever a tire is replaced.


Underinflation or overloading creates excessive stresses and heat, and can lead to tire failure. This could result in vehicle damage and/or serious injury or death. Proper inflation extends tire life and saves fuel.


Maintain the inflation pressure listed in the vehicle owner's manual or on the tire placard.


Proper Vehicle Loading


In addition to showing the vehicle manufacturer's recommended cold inflation pressure, the tire placard also shows the maximum load of the vehicle. Do not overload your vehicle. Remember, baggage carried on top of any vehicle counts as additional load.


If you are towing a trailer, remember that some of the weight of the loaded trailer transfers to the towing vehicle. This reduces the load that can safely be placed in the towing vehicle. The only sure way to prevent overload is to weigh, axle by axle, the fully-loaded vehicle on reliable platform scales. Vehicle weighing procedures are available in the Recreational Vehicle Tire Care and Safety Guide. Mail a request for this free booklet to Rubber Manufacturers Association, P.O. Box 3147, Medina, OH 44258.


Load and inflation information for popular auto tire sizes may be obtained from your local tire dealer.


INSPECT YOUR TIRES REGULARLY


At least once a month, inspect your tires closely for signs of uneven wear.


Uneven wear patterns may be caused by improper inflation pressures, misalignment, improper balance or suspension neglect. If not corrected, further tire damage will occur. (See examples)




Most likely, the cause can be corrected at your tire dealer/seller or other service facility. If you find a problem and correct it in time, your tires may be able to continue in service.


Certain uneven wear patterns may indicate that the tire has suffered internal structural damage and requires the immediate attention of your tire dealer/seller.


Always remove tires from service when they reach a remaining tread depth of two thirty-seconds of an inch (2/32"). If not corrected, wet weather accidents are more likely to happen due to skidding on bald or nearly bald tires. Also, excessively worn tires are more susceptible to damage from road hazards.


Built-in treadwear indicators, or "wear bars," which look like narrow strips of smooth rubber across the tread, will appear on the tire when that point of wear is reached. When you see these wear bars, the tire is worn out and it's time to replace it.


Inspect your tires frequently. Look for any stones, bits of glass, metal or other foreign objects wedged in the tread. These may work deeper into the tire, cause air loss and allow moisture into the tire structure, both of which can lead to tire failure.


If any tire continually needs more air, have it taken off the vehicle and checked to find out why it is leaking. Damage to the tire, wheel or valve may be the problem.


GOOD DRIVING HABITS


The way you drive has a great deal to do with your tire mileage and safety. So cultivate good driving habits for your own benefit.


Observe posted speed limits.

Avoid fast starts, stops and turns.

Avoid potholes and objects on the road.

Do not run over curbs or hit the tire against the curb when parking.




When You're Stuck


The forces created by a rapidly spinning tire can cause an explosion by literally tearing the tire apart. These forces impact the whole tire structure and can rupture the entire casing. Some vehicles are capable of bringing a tire to this failing point in 3 to 5 seconds.


When stuck on ice, snow, mud or wet grass, the vehicle should be rocked gently back and forth by repeatedly shifting the gear lever from drive to reverse on automatic transmissions, or reverse to second on manual transmissions. Vehicles with ABS systems need to follow the instructions in their owner's manual. This should be done with the least amount of wheel spinning. Never exceed 35 mph indicated on your speedometer. If that doesn't free the vehicle, get a tow.




WARNING

Tire explosions can cause death, personal injury or property damage. Excessive speed in a free-running tire can cause it to "explode" from extreme centrifugal force.






WARNING

Avoid tire spinning. Never exceed the 35 mph point indicated on the speedometer. Do not allow anyone to stand near, or directly ahead or behind, the spinning tire.



Highway Hazards


No matter how carefully you drive, there is always a possibility that you may eventually have a puncture and wind up with a flat on the highway. Drive slowly to the closest safe area out of traffic. This may further damage the flat tire, but your safety is more important.


If you feel a sudden vibration or ride disturbance while driving or you suspect your tire or vehicle has been damaged, immediately reduce your speed. Drive with caution until you can safely pull off the road. Stop and inspect the tire. If the tire is underinflated or damaged, deflate it, remove the tire and rim and replace it with your spare. If you cannot detect a cause, have the vehicle towed to the nearest vehicle or tire dealer to have the vehicle inspected.


Follow the vehicle manufacturer's instructions for jacking up the vehicle, taking off the wheel and putting on the spare. Then drive to a place where the flat tire can be inspected for possible repair or replacement.


After a tire has received a severe impact, such as hitting a curb or pothole, you must have it removed from the wheel and inspected both inside and out for impact damage.


An impact-damaged tire and rim may appear "normal" on the outside, but can fail later after the road hazard injury.


Spare Care


Many late-model vehicles are equipped with temporary spare tires and wheels that are different from your regular tires and wheels. Some may require higher inflation pressure, or the use of special canisters to inflate the tire.


Do not exceed 50 mph with a temporary spare. You may operate a vehicle with such a tire within the limits indicated on the sidewall of the tire, until it is convenient to repair the disabled tire or replace it with one of the same size designation and construction as the other tires on the vehicle.


Consult your vehicle owner's manual and the tire sidewall for instructions on proper use of a temporary spare.


Check the inflation in your spare tire every time you check all the others. A spare tire with no air in it is no help to you in an emergency. If you have an inflatable spare, be sure to check the aerosol air inflation pressure canister to be sure it has not been damaged. If so, have it checked by an expert.


Remember, improper mounting and overinflation may damage the tire or wheel and can result in an explosion that could cause serious injury and death. (See safety warning, page 4.)


Run Low Tires


Certain new automobiles may be equipped with tires that can be run with reduced or zero air pressure for a limited number of miles at reduced speeds. Once a tire has been run at reduced or zero pressure conditions, it must be replaced or demounted and inspected to determine if it is reusable, depending on the tire manufacturer.


Aerosol Inflators


Do not depend on tire aerosol sealants and inflators to fix a damaged tire permanently. These products are designed to provide only a temporary, emergency repair to help get you off the road and to the nearest tire repair facility.


Some aerosol products of this type use flammable gases, such as butane, propane or isobutane as propellants. Never, under any circumstances, introduce a flammable substance into a tire. Be sure to inform tire service personnel if you have used any aerosol product to inflate your tire.


VEHICLE CONDITIONS AFFECTING TIRES


There is a close working relationship between your tires and several mechanical systems in your vehicle. Tires, wheels, brakes, shock absorbers, drive train, steering and suspension systems must all function together to give you a comfortable ride and good tire mileage.


Balance


An unbalanced wheel and tire assembly may create an annoying vibration when you drive on a smooth road and may result in irregular treadwear.


Alignment


Misalignment of wheels in the front or rear, improperly operating brakes or shock absorbers, bent wheels, worn bushings and other mechanical problems cause uneven and rapid treadwear and should be corrected by a qualified mechanic. Front-wheel-drive vehicles, and those with independent rear suspension, require special attention with alignment of all four wheels.


These systems should be checked periodically as specified by the vehicle owner's manual or whenever you have an indication of trouble. .


A bad jolt, such as hitting a pothole, can throw your front end out of alignment even if you had it checked an hour earlier. Such an impact can also bend the rim, causing a loss of air pressure, and damage your tires with little or no visible external indication.


Tire Rotation


Sometimes irregular tire wear can be corrected by rotating your tires. Consult your car owner's manual, the tire manufacturer or your tire dealer for the appropriate pattern for your vehicle.


If your tires show uneven wear, ask your tire dealer to check for and correct any misalignment, imbalance or other mechanical problem involved before rotation.


Sometimes front and rear tires on a vehicle use different pressures. After rotation, adjust individual tire air pressure to the figures recommended by the vehicle manufacturer for the tire's new wheel position-front or rear-as shown on the tire placard in the vehicle. (See page 4.)


The purpose of regularly rotating tires is to achieve more uniform wear for all tires on a vehicle. Before rotating your tires, always refer to your individual owner's manual for rotation recommendations. If no rotation period is specified, tires should be rotated approximately every 6,000 miles, or sooner if signs of irregular or uneven tire wear appear. Have the vehicle checked by a qualified technician to determine the cause of the wear problem. The first tire rotation is the most important.


Some examples of popular rotation patterns are shown in the diagrams shown here.


Do not include a "Temporary Use Only" spare tire in any of the rotation patterns shown. If you have a matching full-size tire as a spare and wish to include it in the rotation process, use one of the patterns shown. Insert the spare in the right rear position and place the tire that would have gone on the right rear in the trunk as the new spare.


Some tires cannot be rotated in the manners described. Such tires include uni-directional tires and tires with asymmetric tread designs. Also, some vehicles may have different-sized tires mounted on the front and rear axles, and these different-sized tires also have rotation restrictions. Check your owner's manual, or with your tire dealer or tire manufacturer, for the proper rotation recommendations for these special cases.











THE SIDEWALL STORY


Your tire has very useful information molded into the sidewall. It shows the name of the tire, its size, whether it is tubeless or tube type, the maximum load and maximum inflation, the important safety warning and much other information.


Passenger Tires


Shown on page 13 is the sidewall of a popular "P-metric," speed-rated auto tire. "P" stands for passenger; "215" represents the width of the tire in millimeters; "65" is the ratio of height to width; "R" means radial; "15" is the nominal rim diameter code; and "95H" is the optional service description that consists of the load index (95) and the speed symbol (H). Some older speed-rated tires may include the speed symbol immediately before the "R" instead of showing a service description.


A "B" in place of the "R" means the tire is belted bias construction. A "D" in place of the "R" means diagonal bias construction. "M+S" with the mountain/snowflake symbol is the designation that the tire meets the RMA definitions for use in severe snow conditions. (See page 17).


The maximum load is shown in kg (kilograms) and in lbs (pounds), and maximum pressure in kPa (kilopascals) and in psi (pounds per square inch).


The letters "DOT" certify compliance with all applicable safety standards established by the Department of Transportation (DOT).


Adjacent to this is a tire identification or serial number. This serial number is a code with up to 12 digits that are a combination of numbers and letters. The last characters are numbers identifying the week and year of manufacture. (Example: "1501" means fifteenth week of the year 2001.)


The sidewall also shows the type of cord and number of plies in the sidewall and under the tread.


The DOT requires tire manufacturers to grade passenger car tires based on three performance factors: treadwear, traction and temperature resistance.


Treadwear


The treadwear grade is a comparative rating based on the wear rate of the tire when tested under controlled conditions on a specified government test track. A tire graded 200 would wear twice as long on the government test course under specified test conditions as one graded 100. It is wrong to link treadwear grades with your projected tire mileage. The relative performance of tires depends upon the actual conditions of their use and may vary due to driving habits, service practices, differences in road characteristics and climate.


Traction


Traction grades, from highest to lowest, are AA, A, B and C. They represent the tire's ability to stop on wet pavement as measured under controlled conditions on specified government test surfaces of asphalt and concrete.


Temperature


The temperature grades, from highest to lowest, are A, B and C. These represent the tire's resistance to the generation of heat when tested under controlled conditions on a specified indoor laboratory test wheel.


Light Truck Tires


Shown below is typical information on the sidewall of a light truck tire.


"LT" stands for Light Truck, "LT235/85R16" is the size designation for a metric light truck tire.


"M+S" with the mountain/snowflake symbol is the designation that the tire meets the RMA definition for use in severe snow conditions. (See page 17).


"LOAD RANGE D" identifies the load and inflation limits; RADIAL indicates that the tire has a radial construction. "MAX LOAD SINGLE 1192 kg (2623 lbs) AT 1470 kPa (65 psi) COLD" indicates the maximum load rating of the tire and corresponding minimum cold inflation pressure for that load when used as a single. For normal operation, follow pressure recommendations in owner's manual or on vehicle placard; "MAX LOAD DUAL 1082 kg (2381 lbs) AT 1470 kPa (65 psi) COLD" indicates the maximum load rating of the tire and corresponding minimum cold inflation pressure when used in a dual configuration. The other markings on the sidewall have the same meaning as described for the passenger car tire.







REPLACEMENT TIRE SELECTION


IMPORTANT: Always check the vehicle manufacturer's recommendation before replacing a tire with a different size and/or construction.


Tire Registration


When buying new tires, be sure to ask your dealer for a registration form. The tire dealer/seller fills out their name, address and the DOT tire identification number of each tire sold. Then you just enter your name and address, apply postage and mail it to the manufacturer or its record-keeping designee. Some tire dealers/sellers fill out the form for you and send it electronically. Tire registration will ensure that you will be notified promptly in the event the tire manufacturer needs to contact you.


What Tire is Right for Your Vehicle


When tires need to be replaced, don't guess what tire is right for your vehicle.


For the answer, first look at the tire placard. As you will see, that placard tells you the size of the tires that were on the vehicle as original equipment.


Tires should always be replaced with the same size designation, or approved options, as recommended by the automobile or tire manufacturer. Never choose a smaller size, with less load carrying capacity than the size on the tire placard. Always have tires mounted with the same size and construction designations on the same axle.


It is recommended that all four tires be of the same size, speed rating, and construction (radial or non-radial). However, in some cases, the vehicle manufacturer may require different-sized tires for either the front or rear axles.


When two radial tires are used with two non-radials, put the radials on the rear axle.


There are three types of tire constructions.


Speed Ratings


Many of today's tires are marked, as part of the service description, with letters to indicate their speed rating, based on laboratory tests which relate to performance on the road. Tires may be marked with one of these speed symbols, M, N, P, Q, R, S, T, U, H, V, W and Y to identify the particular tire's speed rating. Additionally, the letter Z may appear in the size designation (see chart below).


When replacement of tires is required, consult the vehicle manual or tire placard for proper size and speed rating (if required).


If the vehicle manual placard specifies speed-rated tires, the replacement tires must have the same or higher speed rating to maintain vehicle speed capability.


If tires with different speed ratings are mounted on the same vehicle, the tire or tires with the lowest rating will limit the tire-related vehicle speed.


Tire speed ratings do not imply that vehicles can be safely driven at the maximum speed for which the tire is rated, particularly under adverse road and weather conditions, or if the vehicle has unusual characteristics. Never operate a vehicle in an unsafe or unlawful manner.



SPEED SYMBOL


MAXIMUM SPEED


APPLIES TO
Passenger Car Tires


APPLIES TO
Light Truck Tires







*above 149 mph (240 km/h)


YES







Y**


186 mph (300 km/h)


YES







W**


168 mph (270 km/h)


YES







V (with service
description)


149 mph (240 km/h)


YES







H



130 mph (210 km/h)


YES


YES



U


124 mph (200 km/h)


YES


YES



T


118 mph (190 km/h)


YES


YES



S


112 mph (180 km/h)


YES


YES



R


106 mph (170 km/h)






YES



Q


99 mph (160 km/h)






YES



P


93 mph (150 km/h)






YES



N


87 mph (140 km/h)






YES



M


81 mph (130 km/h)


YES
Temporary Spare tires








*For tires having a maximum speed capability above 149 mph (240 km/h), a "ZR" may appear in the size designation. For tires having a maximum speed capability above 186 mph (300 km/h), a "ZR" must appear in the size designation. Consult tire manufacturer for maximum speed when there is no Service Description. Example: P275/40R17 93W at 168 mph (270km/h) or P275/40ZR17 at above 149 mph (240 km/h). Consult tire manufacturer.



**A "ZR" may appear in the tire size designation.


NOTE: For "V", "W", or "Y", and tires with a "ZR" rating, a vehicle load adjustment (for speed) is required; consult tire manufacturer.



Types of Tire Construction


Tires should be of the same size, construction (radial, non-radial) and speed rating, unless specified otherwise by the vehicle manufacturer. Tires influence vehicle handling and stability.


Match tire size designations in pairs on an axle (or four tires in dual application), except for use of a temporary spare tire.


If radial and non-radial tires are used on a vehicle, put radials on the rear. If radial and non-radial tires are used on a vehicle equipped with dual rear tires, the radials may be used on either axle. Never mix radial and non-radial on the same axle except for use of a temporary spare tire.


Snow tires should be applied in pairs (or as duals) to the drive axle (whether front or rear) or to all positions. Never put non-radial snow tires on the rear if radials are on the front, except when the vehicle has duals on the rear. If studded tires are used on the front axle, they must also be used on the rear axle. On front-wheel-drive or performance vehicles, it may be advisable to install snow or all season tires on all wheel positions to maintain consistent handling in snow conditions.


Match all tire sizes and constructions on four-wheel-drive vehicles.


COLD WEATHER DRIVING


Many parts of the U.S. have cold-weather driving conditions at least part of the year. Here are some things you should know about cold-weather driving.


How Cold Temperature Affects Tires


Every time the outside temperature drops 10 degrees Fahrenheit, the air pressure inside your tires goes down about one or two pounds per square inch.


You should check your tire pressures frequently during cold weather and add the necessary air to keep them at recommended levels of inflation at all times.


Never reduce tire pressures in an attempt to increase traction on snow or ice. It does not work and your tires will be so seriously underinflated that driving will damage them.


If one of the drive wheels becomes stuck, the centrifugal forces created by a rapidly spinning tire can cause an explosion by literally tearing the tire apart. Never exceed the 35 mph indicated speedometer speed. Do not stand near the spinning tire.


If your vehicle is stuck and a tow truck is not readily available, gently rock your vehicle back and forth, repeatedly shifting the gear lever from drive to reverse on automatic transmissions, or reverse to second on manual transmissions, while applying gentle pressure to the accelerator. Caution: If you have an anti-lock braking system (ABS) in your car, follow the operational instructions in your owner's manual.


Winter Tires


In snowy areas, many cities and counties have "snow emergency" regulations which are invoked during heavy snowfalls. Check with authorities for the rules in your area. Under some rules, motorists are subject to fines if they block traffic and do not have snow tires on their vehicles.


You can avoid this by equipping your vehicle with snow tires marked with "MS," "M&S," or "M + S" on the sidewall.


If you change to snow tires, be sure they are the same size and construction type as the other tires on the vehicle.


Snow tires should be used in pairs (or as duals) on the drive axle (whether front or rear) or on all four wheel positions. Never put non-radial snow tires on the rear if radials are on the front, except when the vehicle has duals on the rear. On front-wheel-drive or performance vehicles, it may be advisable to install snow or all season tires on all wheel positions to maintain consistent handling in snowy conditions.


In areas where heavy snowfalls are frequent, many drivers carry chains for use in emergencies, or have their tire dealer apply studded snow tires or install tires for use in severe snow conditions.


Most states have time limits on the use of studs. Before installing studded tires, check the regulations in your area. If studded tires are applied to the front axle, they also must be applied to the rear axle.


If you use chains, make sure they are the proper size and type for your tires, otherwise they may damage the tire sidewall and cause tire failure.


Tires designed for use in severe snow conditions generally have tread patterns, structure and materials to give superior performance. These tires are marked with the "M+S" designation plus a mountain/snowflake symbol.


SERVICE ASSISTANCE


When you have a question about tires, or a problem, consult your tire dealer. The dealer is the best source of general information and professional service on tires.


Your dealer has service manuals, wall charts and other industry publications on tire load and inflation, tire repair and tire replacement. Your dealer can provide you with the replacement tires your vehicle needs, balance your tires and repair damaged tires which are repairable. Let the dealer inspect your tires periodically, and diagnose any problem you may have.


Loss of Tire Pressure


When you discover a tire losing air, it must be removed from the wheel by a qualified service person for complete internal inspection to be sure it is not damaged. Tires run even short distances while severely underinflated may be damaged beyond repair.


Punctures up to 1/4 inch, when confined to the tread, may be repaired by trained personnel. These tires must be removed from the wheel, inspected and repaired using industry-approved methods which call for an inside repair unit (patch and a plug).


Plugs vs. Patches


A PLUG BY ITSELF IS AN UNACCEPTABLE REPAIR. The repair material used-for example, a "combination patch and plug" repair -must seal the inner liner and fill the injury to be considered a permanent repair. Never use a tube in a tubeless tire as a substitute for a proper repair.


Individual tire manufacturers may differ on whether the speed category applies to speed-rated tires that have been repaired. Consult the tire manufacturer for recommendations.


Serviceable Tire Injuries


Injuries larger than 1/4 inch must be referred to a full-service repair facility. No repairs to the sidewall of a tire should be made without consulting the tire manufacturer. Improper repairs can cause sudden tire failure.


Air loss due to punctures can ruin tires that might have been saved had they been removed in time for proper repair. Gradual air loss raises a tire's operating temperature. This can cause some of the components to separate, or damage the tire body in ways that create rapid or sudden air loss.


Such internal damage may not always be readily apparent and rapid loss of air may still occur despite later installation of a proper repair.


STORAGE TIPS


Tires should be stored in a dry, cool place, away from sunlight and sources of ozone, such as electric motors.


If you must store tires flat, (one on top of the other), make sure you don't stack too many on top of each other. Too much weight can damage the bottom tire.


Also be sure to allow air to circulate around all sides of the tires, including underneath, to prevent moisture damage.


If storing tires outdoors, protect them with an opaque waterproof covering and elevate them from the ground. Do not store tires on or over black asphalt or other heat-absorbent or reflective surfaces, such as snow-covered ground or sand.


For more information on tire care and safety, contact:
The Rubber Manufacturers Association
1400 K Street, NW
Washington, DC 20005
(202) 682-4800
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Old 03-20-2005, 01:23 PM
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