Choosing the correct tire size isn’t only about making the driving experience smoother but looking out for the safety of passengers and those on the road. Opting for a slightly smaller or larger size may not seem like a big deal.
But we assure you, even the slightest difference in size could have the most severe repercussions. If your tire isn’t identical to the ones the company suggested, you’re endangering the lives of those on the road with you.
In addition to a serious safety concern, here are a few other factors affected by the use of the wrong size:
Additional cost for replacing with a bigger tire
Greater surface area results in an even distribution of pressure. This is why bigger ones provide a smoother driving experience.
You feel like your vehicle is gliding along the road. But you can’t expect to go against the manufacturer’s instructions and face no harm.
Installing bigger tires means higher sidewalls. It damages your vehicle’s suspension system, stability system calibrations, and the wheel. But that’s not all. A taller tire influences the speedometer ratings to show a figure much slower than the actual speed.
Incorrect speed reading can be detrimental to everyone involved. Not only will you collect a bunch of speeding tickets, but you also risk the lives of those around you.
Stability and traction deterioration
You may have heard a direct correlation between stability and tire size. So a bigger ones should result in excellent stability, right?
Except that’s not always the case. Using the wrong size messes with the center of gravity of your vehicle. So every time you take a turn, the risk of completely losing control of your vehicle increases.
Higher risk of accidents with smaller tires
Choosing a smaller tire is just as damaging as opting for a bigger one. A small one also influences the speedometer ratings, giving inaccurate speed readings.
As a result, there is a higher risk of the anti-lock brakes malfunctioning, the engine light fusing, and the tire bursting.
How do you know what the right one is?
Reading your tire size may seem like a complicated science. If you don’t understand the meaning of a single element, the entire picture won’t make sense.
But complexity is only limited to understanding the size. When figuring out the size for your car, you won’t have to jump through these many hoops.
You can find your car’s size in two places. First, look at the information sticker on the driver’s side door. Alternatively, you can refer to the vehicle owner’s manual.
You can find the manual in the glove department. Both the sticker and the manual will have complete information about each dimension of the size.
How to read a tire size?
Reading and understanding the size isn’t a skill that only yields a theoretical value but offers practical application. Unlike geometry classes from high school, we assure you that this knowledge will be tested in the real world.
If you’re unable to read tire size, there’s a possibility that you may end up with the wrong size. A tire that doesn’t compliment your car’s settings will deteriorate the car’s performance and stability.
So before you spend hundreds of dollars on a tire only to find out it’s the wrong size, here’s how you can read and understand each element:
We’ll use the tire size ‘P225/70R16 91S’ as an example to break down the meaning of each dimension.
P – The first letter of the code indicates the class to which the tire belongs. Using the example above, we can deduce that the tire is designated for a passenger vehicle. It’s suited for conventional cars, minivans, and SUVs.
If the code had read LT, it would be suitable for a light truck. In contrast, ST-labeled tires would be ideal for special trailers.
225 – The first 3-digit number in the code refers to the tire’s width, measured in millimeters from one sidewall to another. For this particular tire size, the width is 225 mm.
70 – Following the width is the aspect ratio, also known as the profile size. The aspect ratio measures the height of the sidewall as a percentage of the width. For example, an aspect ratio of 70 suggests the sidewall height be 70% as high as the tire is wide.
R – The second alphabet in the code refers to the construction type. R stands for radial structure, made of radial plies running perpendicular to the movement’s direction. They’re made of a mix of fabric, steel, and rubber. The only other type is type D, which is made of plies forming a crisscross pattern.
16 – The two digit-value next to the construction type is the wheel’s diameter, measured in inches.
91 – The last number in the code is the load index or service description rating. The value indicates the weight capacity. You can find the corresponding weight in pounds by using a conversion chart.
S – The last element in the code is a letter representing the speed rating. The alphabetical value can be traced to a corresponding speed in mph. For an S speed rating, the maximum speed is 112 mph.
What is the tire aspect ratio?
The tire aspect ratio measures the sidewall’s height relative to the width. The height is the distance between the wheel rim and the top of the tread. In contrast, the width is measured between two sidewalls.
The height is expressed as a percentage of the width. For instance, an 84 aspect ratio suggests that the sidewall’s height is 80% as high as the tire is wide.
What does 265/70R7 mean?
The tire size ‘265/70R7’ provides information about multiple elements, which is crucial to understanding the size. The number 265 refers to the width in millimeters. Followed by 70, which is the aspect ratio.
It suggests that the sidewall’s height is 70% as high as the tire is wide. The letter R refers to the construction type. Lastly, the single digit 7 measures the wheel’s diameter in inches.
Types
To an inexperienced driver, all the tires look the same. But you may be surprised to find a wide variety in the market. Depending on the function and the terrain, you’ll have to choose accordingly. So here are all the types you need to know of:
Performance
If you’re looking to improve the overall driving experience, there’s no better type than performance tires. They’ve distinct tread patterns designed to enhance the grip and responsiveness to the road. With these on, you’ll feel like you’re gliding on an icy lake.
Pros
- Lesser stopping distances
- Adds safety to fast and furious rides
- Adds convenience.
Cons
- Poorer fuel economy
- Prone to rim and rubber damage.
Touring
Touring tires are perfect if you’re looking for an option that doesn’t betray you when it gets too cold out. T
hey’re designed with better wet/dry traction, allowing long-distance travel smoother than ever. In addition, you won’t have to worry about switching to another type once the snow settles with their high all-season rating.
Pros
- Better traction
- Good handling
- Longer and quieter life on the road
- Compared to all-terrain tires, these are the ones you want.
Cons
- More expensive than regular tires
- Cannot improve stopping distances
Winter
Despite all-season tires’ best efforts, it might not be suitable for you. Winter tires are specifically created to improve traction in snow and ice.
With deeper treads and irregular edges, winter tires guarantee a smooth experience even when the road is covered in thick snow.
Some advantages of winter tires are:
- Enhanced cornering stability
- Increased grip on icy roads
- Increased resistance to hydroplaning
- Quieter ride compared to all-season tires
All-terrain
Driving on smooth surfaces requires no particular skill or equipment, but things get much more complicated when driving on rough terrains.
If you’re worried about your vehicle’s performance on uneven roads, we suggest investing in all-terrain tires. Their complex tread patterns can handle different driving conditions, from sand and gravel to broken roads.
Special service
Special service tires are your best bet if you’re scared of getting stuck in a quicksand situation.
They’ve outward and pointy treads designed to carefully handle damp soil conditions. The design prevents any mud from clogging the structure and inhibiting smooth movement.
Track
For race fanatics, regular tires don’t provide the same thrill. So if you’re looking for speed, track tires will perform tremendously. They offer much better grip and ensure a safe driving experience even when you’re going at 30 mph.
FAQ
It means the tire has a 265 mm tread width. The number 70 refers to the ratio between the height of the sidewall to tread width. The inner rim mounting diameter is 17 inches. It’s a radial tire.
It means it has an inner rim mounting diameter of 20 inches and a width of 12 inches. The sidewall is 50% of the tread width.
