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Tread Patterns

Also called tyre tread designs, tyre tread patterns are the arrangement of continuous ribs, independent tread blocks, or grooves, molded into the tread to fine-tune noise, handling, traction and wear. Tyre treads patterns feature different basic designs to help them meet anticipated driving conditions.

Symmetric Tread Patterns
A symmetric tread pattern is the most common and features continuous ribs or independent tread blocks across the entire tread face. Tyres featuring symmetric tread patterns allow using multiple tire rotation patterns.

Asymmetric Tread Patterns
An asymmetric pattern is designed to blend the requirements of dry grip and water dispersal/snow traction where the tread pattern changes across the face of the tire. An asymmetric tread pattern usually incorporates larger tread ribs/blocks on the outboard side to increase cornering stability on dry roads by offering greater contact area. Tyres featuring asymmetric tread patterns allow using multiple tyre rotation patterns.

Directional (Unidirectional) Tread Patterns
A directional (also called a unidirectional) tread pattern is designed to roll in only one direction. It incorporates lateral grooves on both sides of the tyre’s centerline that point in the same direction and result in v-shaped tread blocks. These grooves enhance hydroplaning resistance at high speeds by pumping water more efficiently through the tread pattern. Unless they are dismounted and remounted on their wheels to accommodate use on the other side of the vehicle, directional tyres are to be used on one side of the vehicle and are intended to be rotated from the front axle to the rear axle. If different tire sizes are used on the front vs. rear axle, the tires become location-specific and prohibit tire rotation unless remounted.

Asymmetric and Directional Tread Patterns
Asymmetric and directional tread patterns have v-shaped tread grooves that are offset compared to the centerline of the tire. Tyres featuring asymmetric and directional tread patterns must be treated as directional tyres for tyre rotation. However, if different tyre sizes are used on the front vs. rear axle, they become location-specific and prohibit any tire rotation possibilities.

Tread Depth and Wearing Guide

A Quick and Easy Safety Measure

Make sure to regularly check the tread depth of your tyres and replace them when they are worn. This will guarantee maximum traction and grip, helping you avoid any unpleasant surprises.

Your safety depends on a good level of tread depth because:

  • The tread grooves disperse water from underneath your tyre, helping maintain control
  • The more tread depth you have remaining on your tyres, the more water you can disperse and therefore reduce the risk of aquaplaning
  • Correct air pressure as well as regular vehicle maintenance will ensure your tyres perform at their best for the longest possible time
  • The tread grips to the road, affecting the distance you require for braking

The image below shows how to check the tread depth on your tyre. Each tyre has indicators showing:


Check Your Tyre Pressure Every Month

Correct tyre pressure reduces the risk of losing control of your vehicle. It also protects your tyres from premature wear and irreversible damage to the internal construction.
Tyre pressure can drop due to small perforations, the natural escape of air through the tyre’s components or even from a decrease in ambient temperatures.

So it is important to check it once a month, because:

  • Low pressure increases the risk of damage to your tyres
  • Excess pressure of 20% can reduce the life of your tyre by up to 10,000 kms
  • Correct tyre pressure will even save fuel

The recommended tyre pressure can be found:

  • In the User’s Manual of your vehicle
  • On the labels on the side door beside the driver’s seat
  • In the storage drawer near the driver’s seat
  • On the inside of the fuel flap

But NOT on the tyre. The inflation pressure shown on the tyre sidewall is only the maximum tyre inflation pressure.

How to Check Tyre Size


What do these numbers mean?

205/65 R16 95 V

205 :- Section width
65 :- Aspect ratio
R :- Radial
16 :- Rim diameter
95 :- load rating
v :-speed rating.

What is the width?

205/65 R16 95 V

The width of the tyre.

What is the aspect ratio?

205/65 R16 95 V

The Aspect ratio or profile is the height of the tyre from the rim to the tread area. It’s shown as a percentage of the tread width. In this case the “height” of the tyre is 65% of the width.

What does the R stand for?

205/65 R16 95 V

R is for Radial and tells us the “construction type” of the tyre. It is less important these days as all car tyres are radial. Many years ago we had  “bias ply” or “cross ply” constructions as well and they needed to be able to identify the different types of tyre since they could not be mixed on the same axle. If there is no ‘R’, the tyre is not a radial.

What is the rim diameter?

205/65 R16 95 V

This is the diameter of the rim that the tyre can be fitted to. Internationally rim sizes are still measured and quoted in inches.

What is the load rating?

205/65 R16 95 V

A type of shorthand or scale used to describe the load carrying capacity of each tyre is. The higher the number, the more load the tyre can carry at a higher pressure.

What is the speed Rating?

205/65 R16 95 V

The speed symbol indicates the maximum speed the tyre is capable of running. In the case the V rated tyre means it can run for 240kph. While it may seem excessive having such high speed ratings on tyres in Australia these ratings come almost as a “by product” of more highly developed tyres. A higher speed rating generally improves the tyre’s ability to withstand heat (eg. driving long distances in hot conditions).