How Much is Enough for Los Angeles County Auto Owners? Tire Tread Depth
Jun 26, 2014
Most Los Angeles County drivers know that tires wear out and that the wear has to do with tread depth. Most of us have heard that “bald” tires are dangerous, but most of us picture a tire with no tread at all when we think of a bald tire. And when we take our vehicles in for preventive maintenance, the technician tells us they’re need to be replaced long before all the tread is worn off. Just how much tire tread wear is too much? And how can you tell? Tires are costly and their condition is important to the safe handling of a vehicle, so it’s important for Los Angeles County motorists to know the answers to these questions.
First of all, it’s critical to understand that there may be a legal limit to tread wear. If your tires are worn past this limit, you have to replace them to be in compliance with California auto safety laws. That’s why measuring your tread wear is part of a vehicle safety inspection.
In some jurisdictions, tread must be at least 1.6 millimeters or 2/32 of an inch thick. This standard has been in effect since 1968. But this standard has recently been called into question, and some Lancaster drivers are arguing that it be changed.
The safety issue that has brought this standard under scrutiny is the ability of a vehicle to stop on a wet surface. When a vehicle has trouble stopping, most Lancaster motorists immediately look at the brakes as the source of the problem. But tires are crucial to safe stopping distances because they provide the traction required in a stop.
A tire’s contact with the road surface creates traction, which allows for effective braking. On a wet surface, a tire only has traction if it can get to the road’s surface. So tire tread is designed to channel water out from under the tire to allow it to stay in contact with the road. If the tire can’t shift the water, then it starts to “float.” This condition is called hydroplaning. It is very dangerous for Lancaster motorists since the vehicle won’t stop no matter how hard the driver presses the brakes. Steering control is also lost.
A recent study tested the stopping ability of a passenger car and a full-sized pick-up on a road surface covered with only a dime’s depth of water (less than a millimeter). The vehicles were traveling at 70 mph (112 kph) when they stopped on the wet surface. At 2/32 tread depth, the stopping distance was double that of a new tire. The passenger car was still traveling at 55 mph when it reached the stopping distance it experienced with new tires.
Let’s suppose that you’re on a busy Los Angeles County highway in a light drizzle and a vehicle stops suddenly in front of you. You just bought new tires and you brake hard, missing the vehicle with only inches to spare. If you hadn’t bought those new tires, you would have crashed into that vehicle at 55 mph. That is a major difference.
What if your tires had a tread depth of 4/32? You would have crashed into that vehicle at 45 mph. Still not a good situation. But it’s better.
Now what if you were driving that pick-up truck? You wouldn’t have missed that vehicle in the first place, and you would have crashed at higher rates of speed in both of the other scenarios. The heavier your vehicle, the longer its stopping distance. It’s a matter of physics.
The results of this test has led Consumer Reports and others to ask that the standard for tread wear from 2/32 to 4/32. The increased standard will improve safety on the road and save lives here in California and nationally.
Of course, until the standard changes, you’ll have to decide whether you’ll be willing to replace your tires a little sooner.
You can use a quarter to tell if your tread wear is down to 4/32. Place the quarter into the tread with George’s head toward the tire and his neck toward you. If the tread doesn’t cover George’s hairline, you’re under 4/32. With a Canadian quarter, the tread should cover the digits of the year.
You can measure the 2/32 tread wear with a penny. If the tread touches the top of Abe’s head, it’s at 2/32. Tires are a significant item for Lancaster auto owners when it comes to car care. But their condition has a major impact on safety. We need to decide whether to sacrifice safety for economy. Keeping our tread wear above 4/32 is good auto advice.
Go Big or Go Home: Upsize Your Wheels at The Car Doctors of the Antelope Valley
Jun 20, 2014
A lot of us Lancaster drivers like our vehicles to reflect our personalities. We're picky about color and body style. We'll customize anything from floor mats to window tints to license plates. One popular way for California motorists to customize a vehicle is to get new wheels.
Wheels come in thousands of designs. Custom wheels can add personality, style or sass to a vehicle. Many of these customizations involve getting a bigger wheel.
Fifteen or 16-inch wheels used to be the factory standard, but today, because a lot of Lancaster drivers like the look of larger wheels, many vehicles are available with 17 or 18-inch wheels. Optional wheel packages of 20 inches or more are also available in Lancaster.
If you want to upsize the wheels on your current vehicle, however, you should know it's not a do-it-yourself project. There are factors involved in ensuring your wheel change doesn't jeopardize the safety of your vehicle.
First of all, you need to understand rolling diameter. The rolling diameter is the overall height of a tire. If you increase the rolling diameter of your tires when you upsize your wheels, you may have to modify your suspension to make sure the larger tires fit in the space and don't rub in turns or over bumps. If that's more work than you're willing to do or pay for, then you need to maintain rolling diameter when you change your wheels.
It's not as hard as it sounds. Imagine a doughnut. That doughnut represents rolling diameter, so you can't make the doughnut bigger. However, you can increase the size of the doughnut hole. That gives you a bigger wheel. Tires with reduced sidewall on larger wheels will preserve your rolling diameter.
Rolling diameter is important because your wheels and tires still need to fit inside the wheel well. Also, your speedometer, odometer and anti-lock brakes are all programmed to work with a specific rolling diameter. You'll throw off the readings on your speedometer and odometer if you change your rolling diameter. And for your anti-lock brakes to work properly, your rolling diameter has to be within 3% of factory recommendations. While some Lancaster drivers who upsize may not be concerned about meter readings, throwing off the brake system is a serious safety hazard.
Further, many vehicles in Lancaster are now equipped with electronically controlled suspensions. Changing the rolling diameter will negatively affect this system as well, which can lead to a less smooth ride and lower handling performance as well as safety concerns.
Your friendly and knowledgeable The Car Doctors of the Antelope Valley tire professional may be able to reprogram your vehicle's computer to adjust for a larger (or smaller) rolling diameter.
So to maintain rolling diameter, you'll need tires with a shorter sidewall. These tires will be designed to give the sidewalls the strength they need to maintain ride quality. Consider that doughnut again. As the wheel (the doughnut hole) gets bigger, the sidewall of the tire (the width of remaining doughnut) gets shorter. That means the tire holds less air. The sidewalls have to be made stiffer to compensate for the decreased air capacity.
To improve their strength, the shorter tires will also be slightly wider than your previous tires. But this means you'll have a larger contact patch, or, in other words, a larger area of tire making contact with the road. This can actually increase your handling performance and decrease braking distances. Many California auto buffs customize their wheels just for this reason—they want the improved performance rather than looks or style. If you drive a truck or an SUV around Lancaster, you might be interested in the extra control an upsized wheel can provide.
Now, that larger contact patch still has to fit inside your wheel well without rubbing when cornering or when bouncing over bumps or potholes on Lancaster roads. This is termed fitment, and you may need a few adjustments so your new wheels will fit properly. You may need spacers so that your brakes will fit inside the new wheels, as well.
The Car Doctors of the Antelope Valley tire professionals are experts at mounting, adjusting and customizing wheels. They can give you a lot of good auto advice about wheels and tires and how they affect driving performance and car care. They can help you select wheels and tires that will suit your driving needs and habits.
For example, if you drive off-road around Lancaster, you should consider a higher profile tire. This type of tire will protect your rims from damage while you're bouncing over rocks. Or, if you tow a trailer or haul heavy loads around California, you'll want a tire with a load rating equal to your demands. Your friendly and knowledgeable The Car Doctors of the Antelope Valley tire professional can help you with these types of concerns.
Once you've got your new wheels, have your service advisor at The Car Doctors of the Antelope Valley see if you need an alignment. You don't want those new wheels and your higher performance compromised by poor alignment. Get the most out of your investment by getting the work done right at The Car Doctors of the Antelope Valley in Lancaster.
Last but not least, remember tire pressure. With larger wheels, your new tires will hold less air and they'll need slightly higher pressure. You'll need to stay on top of preventive maintenance and keep them properly inflated. Be sure to check their pressure at least once a week. If you don't keep your tires at their correct pressure, they will wear out really fast. It will also affect your braking and handling performance.
So smile and show off your vehicle around California. Make it all yours. Bumper stickers, vanity license plates, custom wheels — strut your stuff!