Our customers often ask about tyre wear and how to identify tyres that are worn out enough to warrant replacements. So, in today’s blog we are covering the various identifiers for detecting tyre wear. Furthermore, we will also discuss how worn out tyres can affect your car’s driving dynamics. Let’s get started.
The rubberised pattern that you see on a tyre’s surface is called tread. These patterns are designed to maximise a tyre’s grip by evacuating dust, debris and water from the tyre’s surface. With use, the tread pattern starts wearing down, eventually leading to worn out tyres.
Thus, tyre wear is determined by checking the tread depth on a tyre. But how to determine if a tyre has worn down enough to need a replacement?
Tyre makers invented a seemingly simple but important marker known as Tyre Wear Indicators (TWI) to indicate that a tyre needs replacement. TWI are raised rubber bars sitting deep inside the tread channels of a tyre. The bars are spaced evenly throughout the main grooves. As the tread wears down, these bars come closer to the tyre surface. Once the Tyre Wear Indicators are flush with tread pattern, a tyre must be replaced.
Inclusion of Tread Wear Indicators inside the tyre tread has been mandatory in the United States since 1968. India too has regulations governing the inclusion of Tread Wear Indicators on all pneumatic tyres under IS 15636, stating “The pneumatic tyre shall include not less than six transverse rows of tread-wear indicators, approximately equally spaced and situated in the principal grooves of the tread. The tread-wear indicators shall be such that these cannot be confused with the rubber ridges between the ribs or blocks of the tread.”
Alternatively, you can also measure tread depth using a device called Tread Depth Measurement Gauge. This simple tool can be set on a tyre’s surface to measure the tread depth quickly. The results are displayed in millimetres or 32nds of an inch. This means, you will see measurements like "10/32" or "2/32" representing the tread depth in fractions of an inch.
As you know, losing tread depth means losing your hold on the road, which can result in a number of problems for the driver.
Loss of Grip: The most apparent impact of worn out tyres is losing grip, especially on grainy or wet surfaces. Since the tyre lacks the necessary tread depth to evacuate the debris and water effectively, your vehicle becomes prone to skidding when you turn or brake on such surfaces. Accelerating and decelerating the car also become less effective with worn out tyres as the necessary amount of friction cannot be generated due to lack of tread depth.
Hydroplaning: It’s a condition that generally occurs when driving in rain or wet weather. A thin layer of water forms between the tyre’s surface and the road, causing the vehicle to slide. Tread depth plays a very important role in channeling the water layer away and restoring vehicular control. But if you are driving with worn out tyres, the chances of hydroplaning can increase manifold, and may even lead to a mishap.
Punctures: Tread patterns also prevent punctures by protecting the tyre surface from minor debris and sharp objects. But if the tread has worn out, the tyre becomes more susceptible to punctures.
Impact Damage: Similarly, tread pattern also cushions the tyre’s ply and belts to prevent impact damage. A worn out tyre is more prone to impact damage from a raised curb or speed breakers and any large objects on the road.
Cornering/Manoeuvre Performance: Tread depth determines the amount of grip your car tyres have when cornering or manoeuvring at speed. Worn out tyres pose a safety risk, and may cause your car to go off-the-road due to lack of grip.
Reduced Fuel Efficiency: As in the case with acceleration and deceleration, your car will need more power to generate the necessary frictional force for moving the vehicle, and will also lose more energy when slowing down or stopping. This means worn out tyres will have a direct impact on your car’s fuel efficiency the longer you run with them.
Increased NVH: Noise, Vibrations, and Harshness are a measure used by car makers to determine cabin comfort. Worn out tyres can drastically increase the amount of road noise that filters inside the cabin as they lack the cushioning effect provided by the tread depth.
Apart from these issues, worn out tyres can also impact other components of your car, such as increased risk of damage to the wheels or the suspension system. So, at Vredestein, we recommend regular tread depth checks. Even a simple visual inspection before driving can tell you a lot about a tyre’s condition. In conclusion, regular inspections and timely replacements are not just recommended, but essential for ensuring a safe and comfortable driving experience and preventing potential damage to other vehicle components.
