Tires are possibly the most expensive routine maintenance item for any car. For an SUV or pickup truck, it's not unusual for a set of tires to cost more than $600. If you have unusual tires on your car, you can see price tags well beyond that. Let's take a look at tires and see what you can do to save money when buying new ones.This guide addresses the following topics: tire sizes, when to buy tires, tire features, tires needed by car type, caring for tires and buying tires.
TIRE SIZES
Tires have rather complex sizing methods. A typical tire size looks something like this: 205/60-15. The first number is the treadwidth of the tire in millimeters, so a 205/60-15 tire has a treadwidth of 205 millimeters. The second number is the sidewall height of the tire expressed as a percentage of the treadwidth. In this example, the height of the sidewall of the tire is 60 percent of the treadwidth, so a 205/60-15 tire has a sidewall height of 205 X 0.6 = 123 millimeters. As the second number gets smaller, the height of the sidewall gets lower and lower. For example, a 205/50-15 tire has a sidewall height of 102.5 millimeters. The last number is the size of the wheel on which the tire fits. In this case, 15 means that the tire fits a 15-inch wheel.The taller the sidewall is, the softer the tire will ride and the less you will feel small bumps in the road. Traditionally soft-riding luxury cars have tires with tall sidewalls -- for example, such a car might use a tire size of 205/70-15. Generally speaking, taller sidewalls are more comfortable and lower sidewalls are more sporty. If your car now has tires sized 205/60-15 and you want a tire that will give better handling, you might go to a 215/50-15 tire. This new size has wider tread and a shorter sidewall, and will probably handle better at the cost of the firmer ride.
If you have a pickup or SUV, you should probably go with light truck (or "LT") tires. These usually have only the first and last numbers, so they are sized something like 235-15LT. That means it is a light truck tire that is 235 millimeters wide and it fits on a 15-inch wheel. Light truck tires usually do not have any options for sidewall height -- to change sidewall height on a truck, you usually must buy passenger car tires.
Speaking of which, I generally recommend that you use light truck tires on a pickup or SUV. If you have a small pickup or SUV (such as a Ford Ranger or Escape, Chevy S-10, Honda CR-V, Toyota Tacoma, etc.) and never take it off the road, then you can use a passenger car tire. The benefits are that passenger car tires generally are quieter and more comfortable than light truck tires. However, you can not go off the road with passenger car tires and you should not plan to run the truck frequently at maximum load with passenger car tires. If you have a mid- or full-size pickup/SUV, always use light truck tires unless the vehicle's manufacturer approves otherwise.
WHEN DO I NEED TIRES?
Tires are considered worn out when they have less than 1/16-inch of tread remaining. Most modern tires auto part have wear bars that run across the tread -- a tire is worn when the wear bar is worn even with the tread. In most cases, tires will make a roaring noise when the tires are worn. If your car is a lot noisier than you remember it used to be, check the tires as they may be the culprits. I have had at least two cars that roared noisily down the road, and the "problem" turned out to be worn tires.
Once a month, take a look at your tires and check for wear. 1/16-inch is not very much tread, so if the tire looks nearly bald, it's time for new tires. Keep in mind that most cars today have front wheel drive, which usually wears out the front tires faster than the rear tires. Check both the front and rear tires once a month. Follow the car manufacturer's recommendations for rotating tires, which distributes the wear evenly for front and rear tires.
WHAT ARE THE FEATURES OF TIRES?
Tires auto part have a great deal to do with the performance and comfort of your car. The right tires for you will give your car the handling, braking performance, traction and ride comfort that you want. If you're happy with your current tires -- if the tires now on your car do everything you want the tires to do and the price fits your budget -- then buy another set of tires just like them. Buy the same brand, model and size, and don't let a tire salesman talk you into something else, unless that exact tire is no longer made. Sadly, this happens all too often.If you're shopping for a new set of tires and don't want the exact same ones as those now on your car, then there are several things that you need to consider when you go shopping for tires. The first of these has to do with a rating system known as Uniform Tire Quality Grading or UTQG. The UTQG system rates tires for traction, temperature and treadwear. Note that tire manufacturers test tires for their UTQG ratings, not the government. This means that the fox is guarding the henhouse, so to speak, and you should not place undue confidence in UTQG ratings. However, UTQG ratings are the best we have at the moment.
WHAT UTGQ RATINGS MEANS
Treadwear: A tire rated 200 for treadwear will have twice the life of a tire rated 100. There is no intended correlation between the treadwear number and the number of miles that you will get from a tire.
Traction: Traction can be rated AA, A, B or C, with AA being the highest rating and C being the lowest rating. This rating is for the tire's braking traction on wet pavement. It is not intended to indicate the traction of a tire during cornering or acceleration, only its performance while braking on wet pavement.
Temperature: Temperature can be rated A, B or C, with A being the highest rating and C being the lowest rating. This measures the tire's ability to withstand the effects of heat during high-speed driving.
If you look at the UTQG for a tire, you might see ratings like this:
Treadwear: 440
Traction: A
Temperature: A
All things considered, you want to get tires with the highest UTQG ratings possible, as long as they are within your budget and appropriate for your car. Remember that tire manufacturers measure their own tires for the UTQG ratings, and that the actual ratings represent specific qualities of a tire. Don't assume that tires auto part with a traction rating of A will get you through corners faster than tires with a traction rating of B. The traction rating only measures a tire's stopping ability on wet pavement. The traction rating also says nothing about a tire's ability to handle snow or ice. In fact, there is no measurement or rating that's widely used to quantify a tire's ability to handle icy conditions.
Two other important features of tires include its speed rating and its pressure rating.
SPEED RATING
Most tires for passenger cars are rated "S" or "T" for speed, while performance tires have speed ratings such as "V" and "Z." Here's what these letters mean with respect to the maximum speed rating for a tire:
Designation Speed
Q 99
R 106
S 112
T 118
U 124
H 130
V 149
W 168
Y 186
In addition to these ratings, tire manufacturers sometimes use the letters VR to indicate a maximum speed capability of more than 149 mph. Tire manufacturers always use the letters ZR to indicate a maximum speed capability of greater than 186 mph. Note that a tire with a speed rating of "H" has a higher speed performance rating than a tire rated "T.
In addition to its ability to handle speed, the speed rating of a tire also gives some indication of the tire's sidewall stiffness. Tires rated with speed ratings of H and higher generally have stiffer sidewalls than tires with lower speed ratings. This means that tires with speed ratings of H, V, W and Y almost always give a stiffer ride than tires rated S or T. On the other hand, tires rated H, V, W and Y almost always have better cornering characteristics than tires rated S or T. If you want a sportier ride and crisper handling, get tires that have speed ratings of H, V, W and Y. If you want a softer ride and average handling, get tires with speed ratings of S and T.
