Tires – Understanding the Sidewall – Tire Sizes and Info

How to Read a Tire Sidewall

Tires are confusing. At Pacific Mazda, we carry tires from most major manufacturers and we specialize in knowing which ones are best suited to your Mazda, your driving habits, and the types of driving conditions you are likely to experience in Greater Victoria and on Vancouver Island.

The starting place when you are looking for new tires is to check what you currently have on your car, and to check the recommended tires in your Mazda’s Owners Manual. Mazda does not make tires – there is no such thing as a “Mazda tire” but major manufacturers such as Toyo, Pirelli, Michelin, etc. all make tires in their line that are best suited to certain models of Mazda vehicles.

Tire size is expressed something like this:

P185/75R14 82S.

You can find these numbers and letters on the sidewall of your tire – see the diagram above.

Those numbers and letters can seem like Greek, so let’s define them one at a time.

P: The first letter stands for the tire’s intended use. P is the most common and it means Passenger. LT stands for Light Truck. An LT tire has a sturdier construction than a P tire, and it can carry a greater load, which we will talk about later.

185: The width of the tire, from sidewall to sidewall, in millimeters. A 185 is 185 millimeters, or 18.5 centimeters, wide. The tread width is actually somewhat smaller than the tire’s actual width.

75: Aspect Ratio. This is the sidewall’s height from the inside diameter to the outside diameter. It is expressed as a percentage of the width. A 185/75 is 75 percent as tall as it is wide, making it approximately 138.75 millimeters tall. As aspect ratios decrease, the tire’s firmness increases. Smaller aspect ratios, such as 35 or 40 are generally reserved for performance tires on sports cars.

R: The tire’s type of construction. R stands for Radial, and all new cars and light trucks today use radials. You may also see B in this spot for Bias Ply. Bias ply tires were used prior to the mid 1970s.

14: The tire’s inner diameter, which matches the outer diameter of your car’s wheels.

82: Load Rating. Load ratings range from 0 to 279 and each has a corresponding weight associated with it. A 82 load rating means that tire is certified to carry up to 1050 pounds at maximum inflation pressure. If a car weighs 4000 pounds, then each tire handles 1000 pounds with no passengers or cargo aboard. If you intend to tow a heavy boat or trailer, you should buy tires with a higher load rating. This will require some math to figure out the vehicle weight, the trailer weight, and the weight of a load you may carry inside the vehicle while towing. Add it all up, divide by four, and make sure your replacement tires have a corresponding load rating.

H: Speed Rating. All passenger tires have a speed rating expressed as a letter. Those letters and the corresponding speeds the tires are capable of are included in this chart:
S: 112 mph
T: 118 mph
U: 124 mph
H: 130 mph
V: 149 mph
W: 168 mph
Y: 186 mph
Z: over 186 mph

A Speed Rating is really an indication of a tire’s ability to dissipate heat to avoid a blowout. Higher speeds mean greater heat buildup. Tires with higher speed ratings are constructed to handle heat better. In general, they also ride harder than tires with lower speed ratings. S-, T-, and U-rated tires are considered regular passenger-car tires. H- and V-ratings are reserved for touring tires, which are generally found on sport sedans. The Z rating is for performance tires found on sports cars.

M+S: Mud and Snow. This is an all-season tire. A summer performance tire would have no designation here.

For more information:

Call our tire experts in the Parts Department at Pacific Mazda (250) 385-5747.

Also check out this excellent information on WikiPedia

Thanks to Bob Mitchell, Parts Manager, for assembling the information in this article.

Winter Tires – A Customer Testimonial

Further to our earlier blog post,  “Do You Need Winter Tires In Victoria?”, we just wanted to share a letter from one of our Pacific Mazda customers.  It really hits home  when we are seeing the snow fly in Victoria. Winter tires may seem like an expensive investment but the added safety and peace of mind are  worth it.

Many thanks to Donna for taking the time to write our Sales Associate, Jamie Elmhirst,  this letter:

Hi Jamie,

 After our winter tire conversation, I had winter tires for my Mazda 3 put on just over a week ago at your service shop.

Yesterday, I drove my 16 year old and two of his buddies up to Mount Washington. Apart from a bit of snow on the Malahat, conditions were great. Until just north of Qualicum Beach, in that 110 km an hour stretch between there and Cumberland. I was travelling along, when I watched a 4Runner in my rearview mirror, coming up fast behind me, spin completely out of control, bounce through the centre ditch to the oncoming lanes (thankfully not hitting anyone) and hit the ditch on the far side. Further along, I came across five vehicles stopped together, several of them ditched, including two four wheel drives ditched sideways, and a man slowing traffic and declaring ‘it’s a sheet of ice, be careful!’ We slowed to 70 but kept going. Before we got to the Mount Washington turnoff, we passed at least 10 more vehicles in the ditch. The entire stretch was scattered black ice patches which were very difficult to detect. I had no moments of spinning or sliding; my tires were fabulous.

My tires paid for themselves yesterday. Especially with not just my own son but with other people’s kids in my car. I just read a statistic from 2005 that only 28 percent of BC`ers buy winter tires. I don`t know if that number has changed much, but with the entire BC Interior in that statistic, it is likely a really low percentage for the Island. It might be hard to justify the cost (at $1000, not a small investment) but I now understand that it really makes a difference. It also seems that I couldn’t have planned for the conditions as there doesn`t seem to be a reliable `road conditions` website and I haven`t in fact seen any news coverage of how bad that stretch of road was yesterday.

I just thought I would share since it was our conversation about it that had me decide to buy the tires. Thanks so much!



**For more great Winter Driving information – check out these Winter Driving tips from the Ontario Government website. They have mare experience with winter driving conditions than we do here in BC 🙂

Gislaved Tires From Sweden - It's about time you've heard about them.

Gislaved Tires – The Best Winter Tires You’ve Never Heard Of

Pacific Mazda has recently acquired the Gislaved line of tires in addition to most of the other major brands we already carry. If you are like most people in Victoria and Vancouver Island shopping for winter tires, you’ve probably never hear of this brand.  Well, Bob Mitchell, Parts Manager at Pacific Mazda, has done a lot of the homework for you. He was looking for a high quality winter tire at a reasonable price and he was able to source the Gislaved Nordfrost 5. You can imagine that a Swedish company knows a thing or two about both winter tires and quality.

Gislaved, a Swedish company, is part of Continental AG, Europe’s second-largest tire group, thereby gaining access to truly impressive resources for developing, testing and manufacturing tires. Gislaved  has an enviable reputation for producing some of the world’s best winter tires. That’s only natural, really, considering the hard winters faced in Sweden. By consistently focusing on safety, quality and driving comfort, Gislaved has become successful in more and more markets outside Sweden and today the company has a sales organization that spans the world.

Call Bob or one of the Parts Staff at Pacific Mazda 250-385-5747 for information about pricing and sizes.

Introductory Offer at Pacific Mazda:

Gislaved Nordfrost 5 P205/55/16 16″ winter tires

Set of 4 – $608 – installed

Set of 4 complete with steel wheels – $967 installed

Above prices INCLUDE all taxes – Valid until December 31, 2011

Mazda Steel Wheel Cover Hubcap

Steel Wheel Covers – A cost effective way to make your Mazda look great in all seasons

One of the most practical ways to get winter tires put on your car is to buy an inexpensive set of steel wheels and have your winter tires mounted to them. The only thing about steel wheels is that they are…   for lack of a better word…  ugly

There is a very quick and affordable solution to keep your Mazda looking great even when it has its winter shoes on – some Genuine Mazda Steel Wheel Covers.

This is what a steel wheel looks like without a cover

This is what a steel wheel looks like without a cover

Mazda Steel Wheel Cover Hubcap

This is what a steel wheel with a cover looks like

Do you need Winter Tires in Victoria?

Winter tires are superior to all season tires or summer tires in winter driving conditions for the following reasons:

  • Snow tires have a tread structure that is more aggressive and lets snow clear from the tread
  • Rubber compounds on winter tires are usually softer which allow them to achieve better traction on snow and wet roads
  • Good winter tires shorten braking distance, improve grip when accelerating, and grip better when cornering

Winter tires also contain a special rubber compound mix which allows the rubber to stay softer at lower temperatures, increasing overall grip. As temperatures drop, standard non-winter compounds show decreased elasticity – resulting in a reduced contact area and a decrease in overall grip. The TOYO brand of winter tires such as the Observe GSi-5 also contains crushed black walnut shells embedded in the tread. Why? This environmentally friendly product – which is one of the hardest known natural substances – acts as tiny spikes for increased ice traction. The properties of a winter tire are geared toward cold weather performance, not just snow and ice conditions. A winter tire helps even in the cold, rainy Victoria weather due to the sophisticated rubber compounds and treads.

Do you have all season radials, summer tires, or low profile sport tires?
If you have summer tires or sporty low profile tires, we strongly recommend winter tires on all 4 wheels. Save those other tires for the summer months but don’t trust your safety to them in the rainy, snowy, and icy conditions that you can experience in a Victoria winter.

Is your vehicle front or rear wheel drive?
We find that front wheel drive cars are better in snowy road conditions. Having the engine/transaxle weight right over the driving wheels can help with traction.

Do I need snow tires if I have a vehicle with traction control, stability control, all-wheel drive or 4-wheel drive?
There are a lot of reasons to think your vehicle may not need snow tires, especially on a crossover or sport utility vehicle such as the Mazda CX7, CX9 or Tribute. But even with vehicles that feature 4-wheel drive, traction control, stability control or ABS brakes, the ultimate link between your vehicle and the road is your tires. These features may increase traction when accelerating, but will be of little help when cornering in icy or snowy conditions and of no help when braking. Winter tires provide the best stopping traction in addition to starting and cornering improvements.

I have “all season” tires and this is Victoria which has pretty mild winters – surely I don’t need winter tires?
Snow and ice is often the slipperiest right around the freezing point.  Snowy conditions in Victoria right around 0 degrees C are probably more treacherous than snowy conditions in Calgary at -25 degrees when it comes to traction.
Another factor to consider is that many newer tires have been designed to be “low rolling resistance” tires. While these tire improve fuel economy, they may not provide the handling characteristics desired in wet, cold, and snow/ice conditions.

What is the tread life like on your tires regardless of what type they are?
The condition of your tires must also be evaluated. Worn all season tires may be worse than new summer tires and likewise, old winter tires may not be as good as new all season tires. Get the dealer to give you a good honest opinion on the tread life of your tires. If your all season tires are getting toward mid-end of their life, we strongly recommend getting a set of winter tires. This will also allow you to stretch the life of your other tires.

OK, so I need winter tires. Do I get 2 tires or 4 tires?
If a vehicle has only two snow tires mounted ,lateral traction is still limited to what the other two summer tires are capable of. This can easily lead to fish-tailing – so in almost all cases we recommend getting 4 winter tires and having them aligned and balanced to promote even wear.

Can I get studded snow tires on my car?
Studded tires do provide additional grip on ice and very hard packed snow. In BC, studded tires are not legal since they cause considerable damage to the roads when the roads are not covered with snow and ice. Some of the new tires contain materials such as crushed walnut shells (very hard) embedded into the rubber compound to improve traction.

Are there any disadvantages to putting winter tires on my car in Victoria?
You may notice a slightly rougher ride with a bit more road noise due to the more aggressive tread patterns. You may also notice a slight decrease in fuel economy because of increased rolling resistance. However, the benefits and safety of having winter tires greatly outweigh the disadvantages.

What is the best brand of winter tires for my Mazda?
There is no right answer here and that is why we carry so many major brands. Depending on whether you have a car, truck, SUV, or crossover vehicle, and depending on your requirements and your budget, our experts at Pacific Mazda can make a recommendation that best suits you.
Recommendations from our experts:

For those who drive the Malahat or go skiing to Mt. Washington it’s a necessity…
Get good snow tires on all 4 wheels. Also consider getting them mounted on inexpensive steel wheels that you can put on for the winter and change them back in the spring.

At Pacific Mazda, we have expertise on which tires are best suited to your Mazda vehicle. We also have expertise in properly mounting, balancing, and aligning your tires to meet the manufacturers’ specifications. Selecting and mounting the correct winter tires for your Mazda requires a level of expertise and experience which our staff have.

At Pacific Mazda, we carry most major brands of tires. Our prices are very competitive because we buy so many tires for Mazda vehicles

Here are some starting prices: (As at November 2011)
Mazda 3 snow tires from… $189.00 ea.
Mazda 3 steel wheels from… $80.00 ea.
Mounting and balancing are included at Pacific Mazda with tire purchase.
Buy 4 tires and get a wheel alignment for $79.95

See our Service Team for special pricing on tire and wheel packages and discounts from Mazda and our tire manufacturers.

Tires are one of the best safety investments you can make for your vehicle.

Click for another article  Winter Tires 101