How Often Do People Replace Their Tires? Signs, Mileage, And Best Practices [Update On 2024]

People should replace their tires every six to ten years based on manufacturers’ recommendations. Tire age affects performance even if treadwear looks fine. To find your tire’s age, look for the DOT Tire Identification Number (TIN) on the sidewall. Always consider safety concerns and check for signs of tire failure when deciding to replace tires.

Key signs to replace tires include visible tread wear, bulges, cracks, or sidewall damage. A simple test is the penny test, where you insert a penny into the tread. If you can see the entire penny, it’s time for new tires.

Driving habits significantly impact tire life. Frequent hard braking, sharp turns, and overloaded vehicles can accelerate wear. Seasonal changes, such as winter weather, may also necessitate a switch to winter tires.

Best practices include rotating tires every 6,000 to 8,000 miles and checking tire pressure monthly. Proper alignment and balancing further extend tire lifespan.

Maintaining tire health involves regular checks and understanding when to replace them. In the next section, we will explore the specific types of tires available and how to select the right tires for your vehicle and driving needs.

Table of Contents

How Often Should You Replace Your Tires?

You should replace your tires approximately every six years, regardless of mileage. However, some factors can influence this timeline. First, check the tread depth. If it reaches 2/32 of an inch or less, replace the tire immediately. Second, examine the tire for cracks, bulges, or other visible damage. Any significant wear means it’s time for a new tire. Third, consider the driving conditions. If you frequently drive on rough terrain or in extreme weather, your tires may wear faster. Lastly, check manufacturer recommendations for your specific vehicle and tire type. By following these steps, you ensure safe driving and the best performance from your vehicle. Regular inspections can help you determine the right time for replacement.

What Mileage Markers Indicate It’s Time for Tire Replacement?

Tire replacement is typically recommended every 25,000 to 50,000 miles, depending on various factors.

Tread Depth Indicators
Uneven Wear Patterns
Age of the Tire
Seasonal Changes
Driving Conditions

Tire replacement factors can greatly influence safety and performance. Understanding these factors helps maintain vehicle efficiency and driver safety.

Tread Depth Indicators: Tire tread depth indicators signal when tires need replacing. Most tires have built-in wear bars that become visible when tread wears down to approximately 2/32 of an inch. The National Highway Traffic Safety Administration (NHTSA) emphasizes that adequate tread is crucial for maintaining traction, especially in wet conditions. For example, tires with insufficient tread can double the stopping distance on wet roads.
Uneven Wear Patterns: Uneven wear can indicate alignment or suspension issues and often warrants tire replacement. Common patterns include cupping, which can result from improper inflation or misalignment. According to Tire Rack, recognizing these patterns can prevent further vehicle damage and improve handling. Drivers should regularly inspect tires for wear and consult with a professional if uneven wear is detected.
Age of the Tire: Tires can degrade over time regardless of mileage. The Rubber Manufacturers Association recommends replacing tires every six years, even if tread seems adequate. The materials in tires, such as rubber, deteriorate due to exposure to heat, sun, and ozone. A 2018 study by the AAA found that 28% of Americans were unaware that tires could age out, even if they had not been used extensively.
Seasonal Changes: Seasonal variations can impact tire performance. For instance, winter tires offer better traction during cold months, while summer tires perform well in warmer conditions. AAA advises rotating tires seasonally to ensure even wear and optimal performance. Neglecting seasonal changes may lead to traction problems or increased wear.
Driving Conditions: Harsh driving conditions can affect tire longevity. Roads with potholes, gravel, or excessive heat can accelerate wear. According to a 2020 report from Consumer Reports, drivers in urban areas may need to replace tires more frequently than those in rural areas. It’s crucial for drivers to assess their usual driving conditions and adjust maintenance schedules accordingly.

Understanding these factors enables drivers to make informed decisions about tire replacement, ensuring safety and performance on the road.

How Does Tire Wear Impact Replacement Frequency?

Tire wear directly affects replacement frequency. As tires wear down, their ability to grip the road decreases. This reduction in traction can lead to unsafe driving conditions. Therefore, monitoring tire tread depth is essential. Most experts recommend replacing tires when the tread depth reaches 2/32 of an inch. When the tread wears below this level, tires have diminished performance and safety.

Tires can wear unevenly due to factors like alignment, inflation, and driving habits. Regularly checking tire pressure and maintaining proper alignment helps ensure even wear. Uneven tire wear can further shorten the lifespan of tires, necessitating earlier replacement.

Additionally, driving conditions impact tire wear. Frequent driving on rough terrain or extreme weather can accelerate wear and tear. In these situations, drivers should inspect their tires more frequently and replace them sooner.

In summary, tire wear is a critical factor in determining how often to replace tires. Regular maintenance and monitoring of tread depth can help ensure safety and optimal performance on the road.

What Signs Indicate It’s Time to Replace Your Tires?

Tire replacement is necessary when specific signs indicate reduced safety and performance.

The signs indicating it’s time to replace your tires include:
1. Tread wear indicators
2. Cracks or cuts in the sidewalls
3. Bulges or blisters on the tire surface
4. Uneven wear patterns
5. Age of the tires
6. Vibration or noise while driving

Understanding these signs can help. It is crucial to consider different opinions about tire maintenance. Some may advocate for regular tire rotation to ensure even wear, while others might prioritize inspection frequency based on driving conditions and climate.

Tread Wear Indicators:
Tread wear indicators are small bars formed within the tire tread. These indicators become flush with the surrounding tread when the tire has worn down to 2/32 of an inch, which is considered below the legal limit for safe driving. According to the National Highway Traffic Safety Administration (NHTSA), tires with less than this tread depth have significantly decreased traction, especially in wet conditions.
Cracks or Cuts in the Sidewalls:
Cracks or cuts in the sidewalls can indicate potential tire failure. Sidewalls are crucial for maintaining tire integrity. Diameter and tensile strength decrease with age and wear, leading to a risk of blowouts. A study from the Rubber Manufacturers Association (RMA) highlights that visible cracks may compromise a tire’s lifespan, making replacement essential for safety.
Bulges or Blisters on the Tire Surface:
Bulges or blisters appear due to a weak spot or internal damage. They signify that tire integrity has been compromised. The American Automobile Association (AAA) warns that these abnormalities can lead to sudden tire failure while driving, posing risks to the vehicle’s occupants.
Uneven Wear Patterns:
Uneven wear can be caused by improper inflation, alignment issues, or suspension problems. Identifying uneven wear is crucial because it may cause handling issues and reduce tire longevity. Regular rotation and alignment checks can help address these issues before they necessitate complete replacement.
Age of the Tires:
The age of tires is a critical factor as they can degrade over time, even if tread appears adequate. The RMA recommends changing tires every six years, regardless of tread depth. After ten years, replacement is mandatory, as rubber deteriorates with age leading to increased risks of tire failure.
Vibration or Noise While Driving:
Unusual vibrations or noises while driving can indicate internal tire issues or misalignment. Such symptoms can lead to exacerbated wear and decreased safety. According to an industry survey, many drivers underestimate the importance of responding to these signs, resulting in unnecessary hazards on the road.

By understanding these signs, drivers can ensure optimal tire performance and safety while operating their vehicles. Regular maintenance checks can play a crucial role in preventing premature tire replacements.

How Can Tread Depth Be a Reliable Indicator for Tire Health?

Tread depth serves as a reliable indicator of tire health by reflecting grip performance, water evacuation ability, and overall tire wear. An article by the National Highway Traffic Safety Administration (NHTSA) in 2021 highlights how tread depth directly influences these aspects of tire functionality.

Grip performance: Tires with adequate tread depth enhance vehicle grip on both dry and wet surfaces. According to research by the Tire Industry Association (TIA) in 2020, a minimum tread depth of 2/32 inch is essential for maintaining traction. Tires below this depth can noticeably increase stopping distances, especially on slick roads.
Water evacuation: Tread patterns are designed to channel water away from the tire’s contact patch. Studies by the Rubber Manufacturers Association (RMA) suggest that tires with less than 4/32 inch of tread depth may struggle with hydroplaning. This condition leads to loss of vehicle control as the tires can no longer displace water effectively.
Overall tire wear: Tread depth helps gauge the remaining lifespan of a tire. A study published in the Journal of Automotive Engineering in 2019 emphasized that tires can last approximately 40,000 to 60,000 miles depending on driving habits and maintenance. Regular checks of tread depth can alert drivers to when tires are nearing the end of their usable life.
Safety implications: Insufficient tread depth can significantly heighten the risk of accidents. The NHTSA reported that tires with bald spots or inadequate tread are involved in a higher percentage of road incidents, particularly in adverse weather conditions.

Monitoring tread depth can thus ensure safer driving experiences and prolong the life of tires, ultimately benefiting vehicle performance and safety.

What Other Warning Signs Should Drivers Look For?

Drivers should look for various warning signs that indicate potential vehicle issues. Recognizing these signs can enhance safety and extend the life of the vehicle.

Warning lights on the dashboard
Unusual noises from the engine or brakes
Difficulty steering or a drifting sensation
Fluid leaks under the vehicle
Changes in braking performance
Excessive or uneven tire wear
Dashboard warning messages or alerts
Overheating engine

As each of these warning signs can indicate different problems, it’s essential to understand what they mean.

Warning Lights on the Dashboard: Warning lights on the dashboard provide critical information about vehicle health. Common lights include the check engine light, oil pressure light, and battery warning light. Each light indicates specific issues; for example, the check engine light may signal anything from a minor issue, like a loose gas cap, to a significant engine malfunction. According to a 2021 study by AAA, 32% of drivers ignore dashboard warning lights, potentially leading to costly repairs.
Unusual Noises from the Engine or Brakes: Unusual noises can signal mechanical problems. A grinding noise might indicate brake wear, while a knocking sound from the engine could suggest a more serious issue. Mechanical experts, like those from Consumer Reports, emphasize that prompt attention to unusual sounds can prevent serious injuries and expensive repairs.
Difficulty Steering or a Drifting Sensation: Issues with steering may imply problems with the alignment or power steering system. If the vehicle drifts to one side, it may indicate uneven tire pressure or worn suspension components. Research indicates that 45% of drivers do not regularly check their alignment, which can lead to diminished vehicle control.
Fluid Leaks Under the Vehicle: Fluid leaks can signify various issues, such as coolant, oil, or transmission fluid leaks. Each type of fluid has different implications; for instance, coolant leaks can lead to overheating. A study by J.D. Power in 2020 reported that 30% of vehicle breakdowns are caused by fluid-related issues, emphasizing vigilance for any fluid pools under the car.
Changes in Braking Performance: Any changes in braking performance, such as increased stopping distance or a spongy brake pedal, are serious issues. They may indicate brake pad wear or problems within the brake fluid system. According to the National Highway Traffic Safety Administration (NHTSA), brake failure contributes to approximately 20% of all vehicle crashes, making it imperative to respond to these signs promptly.
Excessive or Uneven Tire Wear: Uneven tire wear can be a sign of improper alignment, overinflation, or underinflation. Regular tire maintenance can prevent further damage. Studies show that properly aligned tires can extend their life by as much as 25%, thereby enhancing safety and performance.
Dashboard Warning Messages or Alerts: Modern vehicles display warning messages that are increasingly sophisticated. These alerts can inform drivers about low tire pressure, maintenance reminders, or engine issues. A 2022 survey indicates that while 78% of drivers pay attention to these alerts, many mistakenly believe they can defer action, which can lead to serious safety risks.
Overheating Engine: An overheating engine typically indicates coolant issues or problems with the radiator. Allowing the engine to overheat can cause irreversible damage. The Engine Performance and Service Journal warns that engine overheating is a leading cause of mechanical failure, emphasizing the importance of monitoring temperature gauges.

Recognizing and responding to these warning signs can help ensure safe driving and maintain vehicle performance.

How Does Tire Age Affect Replacement Recommendations?

Tire age significantly affects replacement recommendations. Tires deteriorate over time, even if they show little tread wear. Manufacturers recommend replacing tires every six to ten years, depending on the tire type and usage. This recommendation arises from the degradation of materials like rubber, which can lead to reduced performance and safety risks.

As tires age, factors like exposure to sunlight, temperature fluctuations, and environmental conditions affect their integrity. Cracks, bulges, or visible wear often indicate the need for replacement. Regular inspections can help identify issues early.

If a tire is older than the recommended age limit, it may fail to perform effectively, regardless of tread depth. Therefore, assessing tire age is crucial for maintaining vehicle safety. Regular monitoring and adherence to recommended replacement guidelines ensure optimal tire performance.

Why Are Tires Subject to Age-Related Deterioration?

Tires are subject to age-related deterioration due to several factors that affect their materials and performance over time. As tires age, their rubber compounds can break down, leading to decreased traction, handling issues, and potential safety hazards.

According to Michelin, a leading tire manufacturer, tires have a lifespan that typically lasts between six to ten years, regardless of tread wear. The Rubber Manufacturers Association also states that environmental influences can contribute to this aging process.

The underlying causes of age-related deterioration include oxidation, ozone exposure, and changes in temperature. Oxidation occurs when oxygen in the air reacts with the rubber compounds in the tire. This reaction can lead to hardening and cracking. Ozone, a reactive gas found in the atmosphere, can also cause rubber to deteriorate, especially at higher temperatures. Additionally, extreme temperature fluctuations can accelerate these processes, further damaging the tire structure over time.

Key technical terms include:
– Oxidation: A chemical reaction where oxygen interacts with materials, leading to degradation.
– Ozone: A gas that can cause rubber to deteriorate by breaking down its molecular structure.

The mechanisms involved in tire deterioration include:
1. Chemical breakdown: The rubber compounds can become brittle and lose elasticity, which decreases traction and increases the risk of tire failure.
2. Physical changes: The tire’s structural integrity may weaken, leading to bulges or cracks.
3. Environmental exposure: Tires exposed to sunlight, extreme heat, or harsh chemicals may deteriorate faster due to increased rates of oxidation and ozone damage.

Specific conditions that contribute to age-related deterioration include improper storage, such as leaving tires in direct sunlight or in an overly humid environment. For example, a tire stored outside in a sunny location may develop cracks sooner than one kept in a cool, dark garage. Additionally, tires that are frequently used in extreme conditions, like high heat or heavy loads, may age more quickly. Regular inspection and proper care can help mitigate some of these age-related issues and enhance safety.

How Can You Determine the Age of Your Tires?

You can determine the age of your tires by checking the tire’s DOT code, visual inspection, and considering the overall tread wear.

The tire’s DOT code provides the most accurate age indication. This code is usually located on the sidewall of the tire. It consists of a series of letters and numbers. Here’s how to interpret it:

Locate the DOT code: The code begins with the letters “DOT”, followed by a sequence of characters and ends with a four-digit number.
Understand the four-digit number: The last four digits represent the week and year of manufacture. For example, if the last four digits are “2319”, this indicates the tire was manufactured in the 23rd week of 2019.

Visual inspection can provide additional clues about tire health. Consider these points:

Cracking or bulging: Check for visible cracks in the sidewall or bulges. These can indicate aging or structural integrity issues.
Tread depth: Use a gauge or the penny test to measure tread depth. Tires should ideally have a tread depth of at least 2/32 of an inch for safe driving.
Age of tires: Even if tread is sufficient, tires typically need replacement every six to ten years, regardless of tread wear according to the Tire Industry Association (2023).

Overall tread wear contributes to the assessment of tire age. Examine the following aspects:

Uneven wear patterns: This could indicate alignment issues.
Tread wear indicators: Many tires have wear bars. When these bars are level with the tread, it’s time for a replacement.

By systematically checking the DOT code, conducting a visual inspection, and assessing tread wear, you can accurately determine the age and overall condition of your tires.

How Can Proper Tire Maintenance Extend Tire Life?

Proper tire maintenance can significantly extend tire life by optimizing tire pressure, ensuring regular rotation, maintaining wheel alignment, and monitoring tread depth. Each of these practices contributes to improved performance and durability.

Tire Pressure: Keeping tires inflated to the manufacturer-recommended pressure enhances fuel efficiency and reduces wear. Under-inflated tires can lead to increased rolling resistance, causing overheating and faster deterioration. According to the National Highway Traffic Safety Administration (NHTSA), maintaining proper tire pressure can improve fuel efficiency by approximately 3.3%.
Tire Rotation: Rotating tires regularly, typically every 5,000 to 8,000 miles, ensures even wear across all tires. Front and rear tires wear differently due to varying load and drive conditions. A study published in the Journal of Safety Research (Brown & Smith, 2021) found that regular rotation can extend tire life by 25% on average.
Wheel Alignment: Proper wheel alignment prevents uneven tire wear caused by misalignment. Misaligned wheels can cause tires to pull to one side and result in premature wear on the tread. The Tire Industry Association recommends checking alignment at least once a year or when experiencing unusual tire wear.
Tread Depth Monitoring: Regularly checking tread depth helps to maintain traction and safety. Tires with insufficient tread depth can lead to poor grip on wet roads, increasing the likelihood of hydroplaning. The Rubber Manufacturers Association states that tires should be replaced when tread depth falls below 2/32 inches for safe operation.

By following these maintenance tips, vehicle owners can significantly enhance the lifespan of their tires, improve safety, and optimize vehicle performance.

What Maintenance Practices Are Essential for Tire Longevity?

The essential maintenance practices for tire longevity include regular inspections, proper inflation, rotation, alignment, and timely replacement.

Regular inspections
Proper inflation
Tire rotation
Wheel alignment
Timely replacement

These maintenance practices are crucial for ensuring the safety, efficiency, and durability of tires over time.

Regular Inspections:
Regular inspections involve checking tires for visible signs of wear and damage. This includes examining the tread depth, looking for cracks or bulges, and ensuring there are no embedded objects, such as nails or stones. A 2021 study by the Rubber Manufacturers Association found that 42% of drivers do not regularly inspect their tires. Regular inspections help identify issues early, potentially preventing tire blowouts.
Proper Inflation:
Proper inflation refers to maintaining the recommended air pressure in tires. Under-inflation can lead to increased tire wear and reduced fuel efficiency. Conversely, over-inflation can cause a harsh ride and susceptibility to damage. According to the U.S. Department of Energy, maintaining the correct tire pressure can improve gas mileage by approximately 0.4% for every PSI (pounds per square inch) drop below the recommended level. It is advisable to check tire pressure monthly and before long trips.
Tire Rotation:
Tire rotation is the practice of changing the position of each tire on the vehicle. This helps ensure that all tires wear evenly. Uneven wear can shorten the lifespan of tires. The Vehicle Maintenance Institute recommends rotating tires every 5,000 to 7,500 miles, or as directed by the vehicle manufacturer. Regular rotation can extend tire life by up to 30%, according to tire manufacturers.
Wheel Alignment:
Wheel alignment involves adjusting the angles of the wheels to ensure they are perpendicular to the ground and parallel to each other. Misalignment can lead to uneven tire wear, steering difficulties, and reduced fuel efficiency. The National Highway Traffic Safety Administration reports that improperly aligned wheels can shorten tire life by as much as 25%. It is recommended to check alignment annually or after hitting a significant road hazard.
Timely Replacement:
Timely replacement occurs when tires are worn beyond safe limits and need to be replaced. The tread depth is crucial for maintaining traction, especially in wet conditions. The general guideline is to replace tires once the tread depth reaches 2/32 of an inch. The Tire Industry Association suggests using the penny test: inserting a penny into the tread; if you can see all of Lincoln’s head, it’s time for new tires. Delaying replacement can lead to dangerous driving conditions and potential accidents.

How Does Tire Rotation Influence Replacement Timing?

Tire rotation significantly influences replacement timing by promoting even tire wear. When tires wear evenly, they maintain optimal performance and extend their lifespan. Regular rotation, typically every 5,000 to 8,000 miles, helps prevent uneven wear patterns.

Uneven wear can lead to a quicker replacement need for the more worn tires. For instance, if front tires are more worn than rear tires, the vehicle may require earlier replacement of the front tires. This timing influences the overall maintenance costs.

By rotating tires, drivers can maximize tread life and delay replacement. This practice ultimately leads to safer driving conditions and better fuel efficiency. Thus, regular tire rotation is essential for timely tire replacement and overall vehicle performance.

When Should Seasonal Tire Changes Be Considered?

When should seasonal tire changes be considered? Seasonal tire changes should be considered when the weather conditions change significantly. Each season presents different driving challenges. For instance, winter tires perform better under cold and snowy conditions. Summer tires provide optimal performance in warmer temperatures.

Typically, drivers should switch to winter tires when the temperature consistently drops below 45°F (7°C). This change prevents winter tires from becoming too hard and losing traction. Conversely, drivers should switch to summer or all-season tires once the weather warms up consistently above this temperature.

It is also advisable to change tires based on local climate conditions. Drivers living in areas with heavy snowfall should consider changing to winter tires earlier in the fall. They should switch back to summer tires by late spring to ensure maximum performance. Regular checks on tread wear and condition are also essential. Tires with insufficient tread should be replaced regardless of the season.

In summary, consider seasonal tire changes based on temperature shifts, local climate, and tire condition. Making these changes at optimal times enhances safety and vehicle performance.

What Factors Determine the Need for Winter or Summer Tires?

The need for winter or summer tires is determined by factors such as climate conditions, temperature variations, driving habits, and regional regulations.

Climate conditions
Temperature variations
Driving habits
Regional regulations

Understanding these factors is essential when making informed tire choices.

Climate Conditions: Climate conditions significantly influence tire choice. Winter tires work best in snowy, icy, or rainy conditions as they are made from specialized rubber compounds that remain flexible in low temperatures. Summer tires are designed for warm, dry conditions and provide optimal handling and braking performance. According to the Tire Rack, winter tires can improve grip on snow and ice by up to 50% compared to all-season tires.
Temperature Variations: Temperature variations play a critical role in tire performance. Winter tires perform effectively below 7°C (45°F), as their softer rubber formulation enhances traction. Conversely, summer tires provide better performance in temperatures above 7°C. Research by Consumer Reports indicates that summer tires can enhance stopping distances by 15% in warm conditions compared to winter tires.
Driving Habits: Driving habits can determine the type of tires needed. Drivers who frequently navigate through inclement weather, such as heavy rain or snow, benefit from winter tires for safety and control. Conversely, those who primarily drive in dry conditions may opt for summer tires, which offer better handling and responsiveness. A study conducted by the National Highway Traffic Safety Administration (NHTSA) found that individuals who drive in urban areas might require different tire types compared to those in rural settings.
Regional Regulations: Regional regulations can influence tire requirements. Some states or countries mandate the use of winter tires during specific months. For example, in parts of Canada, winter tire usage is law from December to March. Understanding local laws is crucial to avoid penalties and enhance driving safety. The Government of Quebec states that winter tires are mandatory from December 1 to March 15, which has been shown to reduce accidents by 10% on average during those months.

How Can Seasonal Changes Affect Your Tire Replacement Schedule?

Seasonal changes can significantly impact tire performance and safety, which consequently affects the tire replacement schedule. Understanding the seasonal variations helps drivers make informed decisions about when to replace their tires.

Temperature fluctuations during seasons cause rubber compounds in tires to behave differently. For example:

Cold Weather: In winter, temperatures drop. Tires made of harder rubber can lose grip and flexibility. According to the National Highway Traffic Safety Administration (NHTSA, 2021), tires underperform when temperatures fall below 7°C (45°F), necessitating winter tire options that provide better traction.
Warm Weather: In summer, high temperatures can lead to increased tire pressure. Under-inflated tires can wear out faster, leading to blowouts. Reports from the Rubber Manufacturers Association indicate that improper tire pressure is responsible for more than 600 fatalities annually in the USA (RMA, 2022).

Tread wear and replacement frequency is also season-dependent. Factors include:

Tread Depth: Under wet conditions, such as during rainy seasons, tires with worn tread lose their ability to channel water effectively. The NHTSA states that tires should be replaced when tread depth reaches 1.6 mm (2/32 inches) to maintain safe performance.
Seasonal Mileage: Drivers often cover more miles during summer vacations. Increased driving can accelerate tread wear and necessitate earlier tire replacements.

Driving conditions linked to seasonal changes can affect tire lifespan. Relevant points include:

Winter Conditions: Snow and ice demand specialized tires. Studies, including one from the Automotive Journal (Brown, 2020), show that vehicles equipped with winter tires reduce the risk of accidents by 35%.
Rainy and Windy Conditions: Increased rainfall in some regions can lead to hydroplaning. Tires with insufficient tread depth pose risks under such conditions.

Regular maintenance checks during seasonal transitions are vital. Scheduled inspections can reveal issues such as:

Uneven Wear: Unevenly worn tires signal alignment problems or improper inflation. Regular inspections can help address these before they require full tire replacements.
Age of Tires: Even if tread seems adequate, tires older than six years can degrade due to environmental factors, thus necessitating replacement.

In conclusion, understanding seasonal impacts on tire performance helps drivers determine optimal replacement schedules for safety and efficiency.

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How Often Do People Replace Their Tires? Signs, Mileage, and Best Practices