18 Apr

I don’t drive over 100 mph

Speed ratings, What the heck?

You walk into the tire store and the sales person tells you that you need a certain speed rating for your car.

You say, “What does that mean?”

She says, “Well, your car came with an H rated tire, you need to stick with that.”

You reply, “You haven’t answered my question, what does it mean?”

She says, “It means the tire can safely travel 130 mph.”

“WHO’s gonna’ drive that fast, not me, I don’t need that!  Give me something else.”  You say.

I have been in the tire business for over thirty years.  I have heard this statement many times.  I have said what the hypothetical saleswoman said many time too, but there really Is more to it.  Does the Speed rating only have to do with speed?  And, should you care?

The answer to the second one is yes, you should.  Generally speaking the higher the speed rating of the tire, the better the tire will handle.  This is not always the case but is generally a good standard to live by.  Therefore, you really should maintain or increase the speed rating of the tire on your vehicle.  If we were to have a braking or cornering rating on the tire, would you willingly downgrade that? No, never.  So why would you downgrade the speed, or as I was taught many years ago “performance rating” of your tire?

4 Nov

Introducing the Toyo Celsius

Introducing the new Toyo Celsius and Celsius CUV.

Toyo built the Celsius as a Variable-Conditions tire. As opposed to the more traditional winter or all season tire, the Celsius and Celsius CUV have been built for year round use and won’t have to be removed when the weather warms. It carries the Mountain Snowflake qualification for severe snow conditions. Unlike most winter products, it has a 60,000 mile tread life warranty. With 22 passenger car sizes and 24 Crossover sizes the Toyo Celsius has the tire to fit your ride. Toyo is so sure you’ll like the tire they backed it with their 45 day/500 mile test drive.


mountain snow flakeIMG-warr-logo-trial[1]

13 Mar

Deciphering Your Tire. The Tire Size

Deciphering Your Tire. The Tire Size


To the lay person, the markings of a tire can look like gibberish. That’s not to say that every person in the business actually has a firm grasp on everything stamped onto a tire either.

The purpose of this post will be to describe and dissect a tire size and show how it fits together to give us its dimensions.

There are several ways to size a tire including numeric, alpha numeric, floatation, and metric. Since the first two are almost exclusively used on antique vehicles, we will discuss only floatation and metric sizing.

Floatation Sizing


I must admit, I love floatation sizing. Why, because it is so simple. The tire is 31 inches tall, 10.50 inches wide, it fits on a 15 inch wheel, and it’s for light trucks.

Metric Sizing:

Metric sizing on the other hand is a bit more cryptic. However, with a little knowledge of how the sizing works and what the numbers and letters mean in the size, you can decipher quite a lot about the makeup of the tire in question.

P225/60R16 98T

P-stands for Passenger commonly referred to as P-Metric. This is used in the US to determine its application. There is also LT for Light Truck, T for Temporary, and ST for Service Trailer. Some tires will have no designation at all. These tires are Euro-metric size tires and they will look like the same size, for example 225/60R16 (no P). However, they aren’t. They will have slightly different load capacities.

Section Width

225–This is a measurement of the widest part of the tire in millimeters excluding scuff guards, rim protectors, etc. This is not necessarily the tread width of the tire, but its widest section.

Aspect Ratio or Profile

60–This is the Aspect Raito of the tire. In other words, the ratio of sidewall compared to the section width.

Rim Diameter

16–this is the diameter of the wheel. In this case, 16 inches.

R-Radial This tells of us its construction. Nowadays, almost every tire is of radial [R] construction.

98T-Service Description This includes the Load Index (98) and the Speed Rating (T). This tells us how much it can carry and how fast you can go on the tire.

Since the main point of this post is to talk about the size of the tire, I’ll leave the construction, load index and speed rating to a later post.

Ok, so how do these numbers go together to form the tire’s dimensions? This may not seem like a very relevant topic to the average consumer who just wants new tires and will never deviate from the factory size. However, it is relevant if you plan on installing a new set of larger diameter wheels or just want to put on a bigger tire.

This formula will tell you how tall a tire is. Overall Diameter–(Section Width X Aspect Ratio X 2)/25.4+Wheel Diameter.   By converting the section width to inches (dividing by 25.4) we know its width in inches(225/25.4=8.86). We can even see what the length of an individual sidewall is with a part of this formula ((225×60%)/25.4)=5.31 inches. In this case the tire is 26.62 inches tall. 5.31+5.31+16=26.62.

I’ve heard over the years from many people so many incorrect assumptions of what the components of a metric tire size are. Hopefully this explains how a tire’s size isn’t just arbitrary, but actually usable data that converts to measurable dimensions of a tire.

3 Feb

The Importance of Checking Your Tire’s Air Pressure

Why check your air pressure?  The tires look ok.  I don’t notice anything when I drive.  The truth is that you should be checking your air pressure at least once a month and before any long drive.

Tire inflation is an important and often overlooked maintenance issue on most vehicles.   According to a 2001 study by NHTSA(National Highway Safety Administration) and NCSA (National Center for Statistics and Analysis), fewer than 30% of passenger car drivers check their tire pressure monthly and 6.56% never check at all.

Why is it so critical to check?

Reduced handling

When a tire is operated with low air pressure it increases the risk of roll over in evasive maneuvers.

Reduced braking ability

Low air pressure increases stopping distance in wet situations and increases the likelihood of hydroplaning.

Lower fuel efficiency

When a tire is low on air its contact with the road increases and its rolling resistance increases due to more friction.  A tires that is only 3% below specification can increase fuel consumption by 1%.

Premature tire wear

A tire that is only 3% below specification can reduce tread life by as much as 10%.

There are several reasons why a tire could be low on air.  Slow leaks can come from small nail punctures, changes in temperature, and natural permeation.  For example a temperature drop of 10 degrees F will result in a 1 psi loss in air pressure.  Also, a tire loses about 1 psi a month naturally.

Nowadays all new passenger cars, CUVs, SUVs, Vans, and light trucks with a GVWR(gross vehicle weight rating) less than 10,000 lbs. are required to have Tire Pressure Monitoring Systems equipped from the factory.  However, don’t rely on the light on the dash to tell you the inflation is incorrect on your vehicle.  While some vehicles’ TPMS will tell you the inflation pressure of each tire, many only alert you if a tire is improperly inflated, plus or minus, by 25%.  You could also have multiple tires improperly inflated and the system cannot tell you.  Don’t forget the air in the spare.  The TPMS light will illuminate on the dashboard if you have a spare tire equipped with a TPMS sensor and that tire’s inflation is off by 25%.

So do your tires, and your wallet a favor and check the air pressure at least once a month.  They’ll last longer, drive more confidently, and use less fuel.

For more information see this informative video from Toyo





Source TIA ATS manual 2005

23 Jan

Air pressure

Where do you find the proper air pressure (PSI) for your vehicle’s tires?

You can find the original equipment (OE) on the vehicle placard, owner’s manual, or on the fuel door. On older vehicles, I’ve even found it in the glove box.
Many people think that the tire PSI stamped on their tires is how much air should go into their tires. This assumption, however well intended, is wrong. The information on the tire shows the maximum pressure you can use, but it makes no assumption on the vehicle usage. The tire that fits your vehicle will most likely fit several vehicles. Each of these vehicles would be a little different in weight and dimension. Subsequently, a tire that is the same OE size fits a variety of vehicles and can have different psi requirements for each vehicle.

Take these different cars for example:
1995 BMW 525i, its original equipment tire is a 205/65R15 94H.
1998 Ford Taurus, its original equipment tire is a P205/65R15 92T.
2000 Honda Accord, its original equipment tire is a P205/65R15 92V.

All use a 205/65R15, but none of them use the same air pressure in their tires.
1995 BMW 525i, its original equipment PSI is 26 psi front and 32 psi rear.
1998 Ford Taurus, its original equipment PSI is 33 psi front and 33 psi rear.
2000 Honda Accord, its original equipment PSI is 30 psi front and 30 psi rear.

None of these cars have the same PSI requirements, but they all drive on a 205/65R15. So the next time you check the air pressure in your tires, make sure to check with the vehicle manufacturer for the correct inflation pressure.

For more information see this informative video from Michelin.