Tire pressure(s) should be checked monthly. Tires can gain or lose pressure depending on driving style, outside temperature and other variables. Improper tire pressure can affect tire wear, gas mileage, and vehicle performance.
To check your tire pressure, you should purchase a good tire gauge. Don’t trust the gauges at the gas stations as they get abused and won’t necessarily give a true reading.
Most cars have a sticker located on the inside door jamb (drivers door), under gas cap door or inside the glove box. This sticker provides you with various information about your car including: the vehicles load capacity, speed rating requirement and most importantly the manufacturer’s recommended tire pressure. This listing is the MINIMUM tire pressure that you should put into your tires. Your car’s owner’s manual should also include this information.
Nitrogen is used for tires on commercial aircraft as well as the space shuttle and some race cars. This is because of nitrogen’s low probability of becoming engulfed in flame and furthering a fire in the vehicle. This is not normally an issue for street driving.
Nitrogen also helps to eliminate moisture from inside the tire. Moisture, in worst case scenarios, can be as high as 5% of the contents of a tire which may speed up the rusting of the actual rim inside the tire. Most cars today use alloy wheels which will not rust and even the vehicles that use steel wheels rarely exhibit rusting so severe as to cause the tire to lose its bead on the rim. So again, not normally an issue.
Tires that can be rotated should be rotated every 6,000 miles. Some cars have a “staggered” fitment meaning that the rear tires are larger than the front tires. Obviously, these tires can’t be rotated and because of that, most tire manufacturers will not honor mileage warranties for these tires.
No is the short answer. But, it is always a good idea to have your wheel alignment checked if your previous tires show any signs of premature wear (uneven wear, more wear to one side and so on). And, if you take it to a quality shop, they will make sure to inspect for any worn suspension parts that could cause future alignment issues.
The tire size can be found on the side of your tire. For passenger vehicles, the size usually starts with the letter P followed by numbers. Light Truck tires (LT) and Special Trailer Service Tires (ST) will have either LT or ST followed by numbers.
To find the manufacture date on your tire, you’ll need to look on the side of the tire near the edge of the wheel. You should see the Department of Transportation Number (DOT). It is a long serial number code that has DOT followed a few letters and numbers. At the end of that code there should be 3-4 numbers in a row. The first 2 of those numbers signifies the week, the last 1-2 signify the year of manufacturing. If there are only 3 numbers at the end of the code, the tire would have been built in the 80’s-90’s and would be of no use.
The tire speed rating is a letter designation given to a tire to signify the speed capability (tested speed capability) of that tire. The most common speed ratings used today are R, S, T, H, V, Z, W & Y. Each of these letter designations are rated for different speed capabilities.
Speed Rating Chart
Load Index is a number designation that refers to the amount of lbs. of weight each tire can carry. As the number designation increases, so does the amount of weight each tire can carry. The Load Index can be found on the sidewall of the tire followed by the Speed Rating which has a letter designation.
For example: 84H (84 is the Load Index & H is the Speed Rating)
The load range or ply rating is a letter designation that is given to all Light Truck (LT) and Special Trailer Service Tires (ST). The load ranges A, B, C, D, and so on, signify the maximum air pressure and load each tire can carry.
As for passenger tires, most are designated as Standard Load (SL) and in some cases they will marked Reinforced (RF) or Extra Load (XL). In most cases Standard Load tires will not be listed on the tire. But, if the tires are either XL or RF they will be listed as such and carry heavier loads than the SL.
UTQG stands for Uniform Tire Quality Guides standard. UTQG is a standardized wear and traction rating and can be found on the sidewall of your tire. The ratings give you a better idea of the quality, life expectancy and performance of each tire.
An example of this would be: Treadwear 400 Traction A Temperature A
Yes. You can replace them individually if you need to replace just one tire.
Yes. You can use the same rims for both run-flat and normal tires. Advantages of using normal tires are:
However, if your car originally came equipped with run-flat tires, more likely than not, your car does not have a spare tire. You need to take this into account and remember that if you get a flat with normal tires, you will either have to call a tow truck, dismount the wheel and have the tire replaced while the car sits where it is, or purchase a spare tire and put it in the trunk thereby taking up storage space.
Maybe. If you get a flat with a run-flat tire, the tire must be inspected to ensure that there has been no damage to the tire itself other than the cause of the flat itself. However, once repaired, tire manufacturers no longer consider the tire to be a run flat as it can’t be guaranteed to be useable as a run flat when needed.
If your car only shakes when you brake, it is most likely not your tires and is an issue with some component of your braking system or suspension.
If your tires are out of balance, it is normally manifested at all speeds or sometimes occurs after reaching a certain speed. But generally it shows up during any use of the vehicle. Accelerating, braking, or coasting.
TPMS stands for Tire Pressure Monitoring System and was first used in 1986 on the Porsche 959. In the United States, the Firestone recall in the late 1990’s pushed the Clinton administration to legislate the TREAD Act. This mandated the use of a TPMS system in all light motor vehicles (less than 10,000 pounds), to help alert drivers to severe under-inflation. All new vehicles sold after September 1, 2007 must have a TPMS system installed by the manufacturer.
If your TPMS warning light lights up (looks like a cross-section of the bottom half of a tire with an exclamation point in the middle), it means that one or more of your tires have pressure that is at least 25% outside the range recommended by the manufacturer. It could be too high or too low, but is generally too low. It could also mean that there is a problem with the monitoring system itself.
Tires that exhibit uneven tire wear do not need to be replaced immediately unless they present a safety hazard. Tires with uneven tire wear may indicate that something is wrong with your car’s alignment, suspension, or even the rims. You should have these things inspected as soon as possible to ensure better tire wear.
Once a tire begins to wear unevenly, it will always have uneven wear and should eventually be replaced. As long as it is safe to do so, you should continue to use the uneven tire until you have had repairs completed otherwise you risk damaging any new tire you purchase.
Chain controls are generally determined by the California Highway Patrol (CHP) and local authorities. Generally, if you have a 4-wheel or all-wheel drive vehicle with snow tires, chains are not required. However, if you have all-season tires as is the norm for most vehicles in Southern California, you will be required to install snow chains over your all-season tires.
Check with the CHP at the specific time and for the specific area that you wish to travel to in order to determine if you need chains.
Most manufactures strongly recommend changing all 4 tires when one or more tires become unserviceable. Their reasoning is, All-Wheel Drive vehicles (AWD) as well as Four Wheel Drive vehicles (4WD) have 2 differentials that want to rotate the front and rear tires at the same rate. If you only replace 2 tires at a time, the 2 replacement tires will more than likely be taller (taller = greater rotational circumference) due to brand and/or tread depth differences. Therefore, the smaller tires will be forced to rotate more revolutions per mile than the taller tires.
The downfall of having 2 tires rotating more revolutions per mile than the other 2 is: puts added stress and could possibly damage the transmission and/or All-Wheel Drive systems. For those reasons, most tire shops and service centers will not replace1-3 tires on both AWD’s and 4WD’s.
Prorated mileage warranty is a warranty that provides a refund towards (warranted mileage-actual mileage=refund percentage) your next purchase of tires if you do not receive the mileage specified by the manufacture. Don’t be fooled, the manufacturers aren’t making it easy for you to collect on this coverage. They set several parameters for this warranty and you must follow their strict guidelines to the “T”.
The most common requirement(s) the purchaser must abide by are; must purchase all 4 tires at the same time, rotate your tires every 5000-6000 miles, maintain proper inflation at all times, maintain vehicles alignment specifications, tires can’t be adjusted unless they have reached 2/32 tread-depth (minimum legal tread-depth) and to top it off, you must have proof of all the above. Then the inspection process occurs, and if it is determined that one or more of the requirements weren’t met, most manufacturers will not be obligated to honor the tread life/mileage warranty.
San Diego, CA