TIRE BASICS

Tire Contact Patch

Tires seem simple – from the outside, they look like a disc of rubber. But tires are highly engineered composite structures and have many critical tasks – two fundamental tasks are to help the driver and the vehicle keep your car connected to the road and support the weight of the vehicle. All of that depends on the contact patch, being the only area in contact with the road.

What is a Tire Contact Patch?

The tire contact patch is the area of a tire’s tread that touches when a tire is pressed against a surface. Generally, the overall size of each contact patch is no larger than the size of your hand.

For a tire with a grooved tread pattern, the contact patch area is composed of both void areas, created by the tread’s groove pattern, and contact area, where the rubber tread elements are pressed against the surface. It’s important to understand that the tire contact patch is not something added to a tire as it is constructed. Instead, it occurs as the result of many highly engineered components, designed and configured to manage loading as a vehicle goes through stop, start and cornering maneuvers.

The ability of a tire to manage these loads through the contact patch, influences many performance attributes including:

Treadwear
Steering Responsiveness
Wet & Dry Handling
Traction
Tire Noise
Ride Quality

There are four contact patch areas on a typical automobile – all of which help to cushion the vehicle from road impacts, provide traction for acceleration and braking, and transmit steering forces. A tire’s contact patch provides this in many different road and weather conditions..

How Does the Contact Patch Impact Tire Performance?

As the forces on a tire change, the tire contact patch also changes. Using the vehicle manufacturer’s recommended tire inflation pressure, assures adequate load carrying capacity and optimal vehicle handling and performance. A tire’s optimal contact patch will be achieved when the tires are inflated properly.

Picture an inflated balloon and lightly press that balloon against a wall. Notice how little of the rubber balloon makes actual contact against the wall? Now, press harder, and you’ll see the balloon conform to the wall, flattening a bit to put more rubber on the wall.

That’s the general principle of what happens with a tire; however, the tire is engineered with special compounds and construction reinforcements that help the contact area conform and influence performance in specific ways when properly inflated.

That’s also why maintaining the proper tire pressure – as found on the vehicle information placard typically located on the driver door pillar, is critical for optimal performance of both your tires and vehicle. Note: The vehicle manufacturer recommended inflation pressure often varies from vehicle to vehicle, even though two vehicles may be equipped with the same tire size. The placard may also specify different inflation pressures between tires on the front axle and the rear axle. Additionally, the inflation pressure found on the sidewall of the tire is the maximum inflation pressure and is not necessarily the inflation pressure recommended by the vehicle manufacturer.

What’s the Difference in the Contact Patch Between a Performance Tire and a Light Truck Tire?

Different vehicles use different tire sizes and types based on how they’ll be used.

For example, a sportscar, which is expected to deliver highly responsive handling when turning, might be best equipped with Goodyear Eagle® F1 SuperCar® 3 tires. This tire is engineered to deliver responsive handling and cornering and are available in wide, low-profile sizes. The wider, low profile sizes result in a contact patch shape that is wide and relatively short, a good match to deliver highly responsive handling and cornering.

On the other hand, a light truck, expected to haul payloads, pull trailers and possibly even navigate some inclement or rugged terrain, might be best equipped with Goodyear Wrangler® All-Terrain Adventure With Kevlar® tires. This tire’s sizing, construction and tread is engineered to haul and navigate inclement or rugged terrain. It is available in the larger and taller sizes suitable for light trucks. These larger, taller sizes result in a contact patch shape that is long, but relatively narrow, a good match to haul pay-loads, pull trailers and navigate rough terrain.

The contact patch on your vehicle changes constantly as your vehicle stops, starts, corners and as the load in your vehicle changes. Vehicle manufacturers select tire sizes, provide recommended tire inflation pressures and provide chassis alignment specifications to deliver a tire contact patch that will provide optimized tire performance as your vehicle goes through these dynamic motions. Additionally, because the loads and forces that your tires experience are different at each vehicle corner, it is also important to properly rotate your tires as recommended in your vehicle owner’s manual. If no rotation pattern is recommended, contact a local tire shop near you today and let one of our professionals assist.

NOTE: Over-inflating or under-inflating your tires versus the vehicle manufacturers recommendation is not advised as this can result in irregular tire wear patterns and may negatively change tire performance. Learn more about correct Tire Air Pressure for your vehicle.

In cases where you wish to change tire sizes from the original equipment size, always consult a tire professional to ensure adequate load carrying capacity.