Types of Treadwear
Why does treadwear even matter?
Wondering why don’t you feel that strong grip of your tire with the road anymore? Maybe your tire tread has worn out. Yes, tread health directly affects the handling of your vehicle. There is a lot of engineering involved in tire designing to give your vehicle the most comfortable ride. Tread is one of the main components of the tire as it makes direct contact with the road.
Ok, got it! But why do we need those grooves in the tires? Those grooves in tires are to increase the traction of the tire with the road. More importantly, these grooves provide passage for precipitation to escape anytime it gets between the tire and the road. This maintains as much contact with the road surface as possible. That’s one of the reasons why winter tires have deeper and more defined grooves to work their way out of water or snow. Shallow grooves mean less area for precipitation to escape and more chances for the tire to slip, creating a condition called Hydroplaning.
Minimum allowed tread depth
Most states in the United States have established a 2/32 inch minimum tread depth requirement. It is recommended to check your tires once a month to check for defects, tread depth, and tire pressure. There are various tools to physically inspect the tread depth of the tire. The most common one is placing a penny with Lincoln’s head upside down in the tire groove. If the head is fully visible then it means the tread depth is below 2/32 inch and it’s time to replace the tire. Another way is to use a measuring tool instead of a penny and that gives you the tread measure in desired units.
The Cerebrum Smart Sensor has this inbuilt feature to automatically check tire’s tread depth regularly to keep you up to date with your tire’s tread health. No more need to set a reminder or dirty your hands to physically inspect your tires. Very cool right? We understand that peace of mind is what everyone aspires to achieve. Cerebrum smart sensor solves such problems and collectively help to deliver a smoother ride.
What causes Treadwear?
Various factors could contribute to early treadwear or irregular treadwear. The most common causes are improper inflation pressure and out-of-spec tire alignment.
Treadwear from Improper Inflation Pressure
Vehicle manufacturers specify the optimum pressure for front and rear tires to get the most comfortable ride, handling, good fuel economy, and proper tire wear. Proper inflation pressure is important to optimize vehicle acceleration, cornering, and vehicle load distribution. Improper inflation pressure leads to two types of treadwear.
The tire shows signs of wear on the edges when it is underinflated. Causing the center of the tread to make loose contact with the road as compared with the tire’s edges.
Tread wears at the center when the tire is overinflated. Causing the tire tread to curve more at the edges and resulting in contact patch narrowing towards the centerline of the tread.
Treadwear from Out-of-Spec Tire Alignment
Tire alignment is not the adjustment of tires or wheels themselves. It refers to the adjustment of the vehicle’s steering and suspension components. Every vehicle has its own manufacturer’s recommended tire alignment specifications for parameters such as camber angle, toe angle, and caster angle. A combination of these three angles gives the tires their most appropriate angle of contact with the road.
There are commonly three types of uneven tire wear from improper alignment:
One-sided Shoulder Wear
This happens from excessive positive or negative camber angle. It is also known as camber wear. Camber changes the lateral dynamic load on the tire surface. This does not accelerate the total wear rate. In this type of tire wear the inside or outside of the shoulder rib which is experiencing more dynamic load is worn significantly more than the other side.
Toe Tire wear
Toe wear physically scrubs one side of the shoulder rib across the road. The physical touch of the tread block feels like saw teeth. Excessive positive or negative toe accelerates the rate of wear. Toe wear is a tire killer.
Feather Edge Tire wear
Feather edge wear occurs due to the improper combination of the excessive toe and caster angle. In this type of wear, tread ribs are worn smoother on one side and sharper on the other.