Driving economically can help you save money on fuel and protect the environment. There are some simple measures you can take to reduce your fuel consumption, such as getting your car serviced regularly, controlling your speed and gear changes, avoiding unnecessary weight, and limiting the use of air conditioning. But one of the most important factors for saving fuel is your tires.

Your tires have a direct impact on your road grip, braking distance, and fuel consumption. Factors such as tire pressure, wear condition, tread type, and quality play a significant role in this.

HOW TO CHOOSE AND MAINTAIN YOUR TIRES PROPERLY

With the right tire choice and care, you can not only save fuel but also drive more safely and comfortably. So what can you do to drive economically with your tires? Here are some tips:

• Check your tire pressure: Underinflated tires require more energy to roll. Furthermore, tires that are loosely mounted on the rim can lose pressure over time.

Optimal tire pressure can save you up to 5% of fuel. Low tire pressure increases friction on the road and thus increases fuel consumption.

Therefore, check your tire pressure at least once a month and adjust it according to the specifications in your vehicle’s owner’s manual.

• Rotate your tires regularly: To monitor the wear of your tires and ensure even wear, you should rotate your tires regularly. Rotating means swapping the front and rear tires. This should be done every 10,000 kilometers.

This way, you can extend the life of your tires, improve road grip, and save fuel.

• Choose fuel-efficient tires: When choosing tires, don’t just look at the price or brand. Also pay attention to the tire labels. These labels provide information about the performance of the tires in terms of wet grip, braking distance, noise, level, and fuel efficiency.

Fuel efficiency is indicated by letters from A to G. A is the best fuel efficiency and G is the worst. By choosing fuel-efficient tires, you can reduce your fuel consumption.

• Use high-quality and reliable tires: The quality and reliability of your tires are crucial for your safety and the performance of your vehicle. Cheap or unsuitable tires can endanger your safety and increase your fuel consumption. That is why we recommend that you select trustworthy brands when buying tires.

OPTIMISE DRIVING STYLE AND LOAD TO SAVE FUEL

Avoid aggressive driving behaviors such as rapid acceleration, hard braking, and high speeds. These driving styles can lead to increased fuel consumption. Instead, practice smooth and gradual acceleration and braking. Here are a few more tips:

• Keep your speed steady:  Maintaining a steady speed can help improve fuel efficiency. On highways, use cruise control to maintain a steady speed and avoid unnecessary speed changes.
• Avoid idling: Idling consumes fuel without any meaningful movement. If you plan to be stationary for more than a minute, it is often better to turn off the engine and restart it when you are ready to continue.
• Reduce ballast: Vehicle ballast can affect fuel efficiency. Remove unnecessary items from the trunk or roof to reduce the overall weight of the vehicle.
• Plan efficient routes: Use navigation systems to find the most direct and efficient route to your destination. Avoid heavy traffic when possible to avoid fuel-wasting stop-and-go situations.

CONCLUSION

If you follow these tips, you can save fuel with your tires. Remember:

Saving fuel for your car starts with the tires. To drive economically, choose your tires correctly and don’t neglect their maintenance.

Tires are the only connection between your vehicle and the road. Therefore, they must be first in good condition to ensure safety and performance. 

But how do you know if your tires are worn or damaged and when to replace them? 

In this guide, you will learn how to check the condition of your tires and how to avoid potential problems.

RECOGNIZING WORN TIRES

Tread depth is an important indicator of tire wear. The lower the tread depth, the worse the grip on wet or slippery roads. It also increases the risk of aquaplaning, or the tire floating on a surface of water. The legal minimum tread depth for summer and winter tires in Germany is 1.6 mm. However, experts recommend changing tires sooner: at least 3 mm for summer tires and 4 mm for winter tires.

There are several ways to measure tread depth. The simplest is to look at the tread wear indicators in the tread grooves. These are small bumps that are 1.6 mm high. If the tread is flush with the wear indicators, the tire has reached its minimum tread depth and needs to be replaced. Another method is to insert a one-euro coin into the tread groove. If the gold edge of the coin is visible, the tread depth is less than 3 mm and the tire should be replaced soon.

In addition to tread depth, you should also consider the age of your tires. Tire life depends on various factors, including driving style, stress, storage, and maintenance. On average, tires last about six years, after which they can become brittle or porous. Manufacturers recommend replacing tires after ten years, even if they are not worn out.

To determine the age of your tires, you can read the DOT number on the tire sidewall. The DOT number is a four-digit number that indicates the date the tire was manufactured. The first two digits represent the week of manufacture and the last two digits represent the year of manufacture. For example, a DOT number of 2219 means the tire was manufactured in the 22nd week of 2019.

RECOGNIZING DAMAGED TIRES

In addition to wear and tear, other factors can cause tire damage. These include:

• Foreign objects: Nails, screws, glass or other sharp objects can penetrate the tire and cause a loss of pressure or sudden blowout. If you discover a foreign object in your tire, do not attempt to remove it yourself, but take it to a service centre.
• Mounting errors: Mistakes can be made when mounting tires and rims, which can result in damage to the tire sidewall or carcass. This can affect the stability of the tire and result in a blowout. Always have a professional install the tire.
• Obstacles: Driving over curbs, potholes or other obstacles can cause abrasions, cracks, or bulges in your tires. These can weaken the structure of your tire and lead to a blowout. Avoid such obstacles as much as possible, or ride slowly over them.
• Inflation pressure: Incorrect inflation can cause premature wear or overheating of your tires. Underinflation can cause cracks in the sidewalls or damage to the casing. Too much pressure can cause uneven wear or a blowout. Therefore, you should check your air pressure regularly and adjust it to the manufacturer’s specifications.

You should check your tires regularly for signs of damage, such as cracks, bulges, cuts, or blisters. If you notice any of these signs, you should have the affected tire replaced immediately.

WHEN TO REPLACE YOUR TIRES

The life of your tires depends on many factors, including driving style, load, storage, and care. On average, tires last about six years, after which they may become brittle or porous. Manufacturers recommend replacing your tires after ten years at the latest, even if they are not worn out.

In addition to age and wear, there are other reasons why tires may need to be replaced. These include:

• The season: Unless you have all-season tires, you should switch between summer and winter tires depending on weather conditions. Summer tires provide better grip and lower rolling resistance in warm temperatures. Winter tires provide better grip and shorter braking distance in cold temperatures and snow or ice. The rule of thumb is: Winter tires should be used from October to Easter.
• The type of vehicle: If you are buying a new vehicle or selling an old one, make sure your tires match your vehicle type. The tire size, speed index and load index must match the information on your vehicle registration. Otherwise, there may be problems with registration or insurance.
• Driving safety: If you notice that your tyres are damaged or your driving performance has deteriorated, you should have your tires changed. This may be the case if you slip more often, experience aquaplaning or have a longer stopping distance. This could be an indication of reduced grip or loss of tire pressure.

CONCLUSION

Tires are an important part of your vehicle and should be checked and maintained regularly. You should pay attention to wear indicators and inspect the tires for visible damage to detect worn or damaged tires.

Maintain the correct inflation pressure, remove foreign objects, avoid obstacles, and have your tyres properly fitted and stored to avoid tire damage. To ensure safe driving, you should change your tyres according to the season, vehicle type and condition.

Tire pressure determines the shape and contact area of the tire on the road. If the pressure is too low; the tire deforms more and has a larger contact area.

This results in higher rolling resistance, higher fuel consumption, uneven wear and overheating of the tire.

The tire also loses stability and grip, resulting in poor handling and braking. In the worst case, underinflation can cause the tire to burst or slip off the rim.

WHY IS PROPER TIRE PRESSURE SO IMPORTANT?

When tire pressure is too high, the tire deforms less and has a smaller contact area. This results in lower rolling resistance and fuel consumption, but also uneven wear and poor tire grip. In addition, driving comfort suffers because the tires are less able to compensate for uneven road surfaces. In the worst case, overinflating can cause the tire to burst.

The correct tire pressure is therefore a compromise between rolling resistance, fuel consumption, wear, grip, driving comfort and safety. It depends on several factors such as vehicle type, tire type, load, speed and outside temperature.

HOW DO I DETERMINE THE CORRECT TIRE PRESSURE?

The correct tire pressure for a vehicle is specified by the manufacturer and may vary depending on the front and rear axle. The correct tire pressure can be found in different places, such as the owner’s manual, on the B-pillar when the driver’s door is open, on a sticker in the glove compartment, or on the inside of the fuel filler cap, depending on the vehicle. You can also find tire pressure charts from manufacturers on the Internet.

Tire pressure is measured in bars. It is customary to indicate the excess pressure over ambient pressure rather than the absolute pressure. A tire pressure of 2.7 bar therefore, means that the tire pressure should be 2.7 bar above the ambient pressure of approx. 1 bar.

The correct tire pressure always refers to the “cold” tire. This means that the tire has not warmed up due to a longer or faster ride. This is because the air in the tire expands as it warms up and the pressure increases. Therefore, the tire pressure should be checked before starting a trip or after a short ride at moderate speed.

HOW DO I CHECK MY TIRE PRESSURE?

To check your tire pressure, you will need a tire pressure gauge. This can be a handy digital or analogue pressure gauge, which you can buy at a speciality shop or online. You can also use a tire pressure gauge at a gas station or auto repair shop to check your tire pressure. Make sure that the gauge is calibrated and suitable for the pressure range you want to use.

To measure the pressure, first remove the valve cap from the valve of each wheel and press the gauge firmly on the valve. As little air as possible should escape. The gauge will now show the current tire pressure. Compare this with the manufacturer’s recommended tire pressure and keep track of the difference if needed. Repeat for all four wheels.

HOW DO I INFLATE THE TIRE PROPERLY?

To inflate the tire, you will need a suitable source of compressed air. This can be a compressor you have at home or in a garage. You can also use an air station at a gas station or repair shop. Make sure that the air source is calibrated and suitable for the desired pressure range.

To inflate the tire, first unscrew the valve cap from the valve of each wheel and press the air gun firmly onto the valve. As little air as possible should escape. The air gun will then display the current tire pressure. If the pressure is too low, pump air into the tire with the air gun. When the tire pressure has reached the manufacturer’s recommended value, release the air gun and pull it off the valve. Then screw the valve cap back on the valve. Repeat this procedure for all four wheels.

If the tire pressure is too high, deflate the tire. You can do this by pressing the tip of a ballpoint pen or another suitable object into the valve to open it. Be careful not to release too much air at once. Check the tire pressure with a pressure gauge and adjust if necessary. Screw the valve cap back onto the valve. Repeat for all four wheels.

HOW OFTEN SHOULD I CHECK MY TIRE PRESSURE?

Tire pressure should be checked regularly and adjusted if necessary to ensure the safety and performance of the vehicle. Check the tire pressure with a tire pressure gauge and adjust if necessary. In addition, tire pressure should be checked before long trips, when there are large temperature fluctuations, when the load changes, or when changing from summer to winter tires.

WHAT ARE TIRE PRESSURE MONITORING SYSTEMS?

Tire Pressure Monitoring Systems (TPMS) are electronic systems that monitor tire pressure while a vehicle is in motion and alert the driver to low tire pressure. As of 1 November 2014, TPMS is mandatory for all new vehicles in the EU. There are two types of TPMS: indirect and direct.

Indirect TPMS uses the vehicle’s anti-lock braking system (ABS) to measure the speed of each wheel. If one wheel is under-inflated, it will spin faster than the others. The system detects this misalignment and alerts the driver via a dashboard display.

With direct TPMS, sensors in each wheel measure the air pressure and temperature in the tire and send the data wirelessly to a control unit in the vehicle. The system displays the current tire pressure at each wheel and warns the driver if the tire is under-inflated or overheating. TPMS are useful tools that can improve safety and prevent damage. However, they do not replace regular tire pressure checks with a proper gauge, as they are not always accurate or timely.

THE BOTTOM LINE

Proper tire pressure is an important factor in the safety and performance of a vehicle. It should be checked regularly and adjusted if necessary to achieve an optimum balance between rolling resistance, fuel consumption, wear, grip, ride comfort and safety.

Tire pressure monitoring systems can help detect and report a loss of pressure while driving, but they do not replace manual checking with a proper gauge.

Compensate for uneven road surfaces. In the worst case, overinflating can cause the tire to burst.

The correct tire pressure is therefore a compromise between rolling resistance, fuel consumption, wear, grip, driving comfort and safety. It depends on several factors’ such as vehicle type, tire type, load, speed and outside temperature.

Tires are an important component of any car. They provide the connection between the vehicle and the road and are responsible for the safety and driving performance of the car. Therefore, it is essential that the tires meet the legal requirements.

Because not all tires are approved for all vehicles. If you mount the wrong tires, you risk not only your driving safety, but also your insurance coverage and a fine. This post will address issues related to tires, such as those you’re allowed to use, how to determine and calculate the size of the tire, and the differences between various sizes of tires.

CALCULATION AND MEANING OF TIRE SIZES

Tire size has a major influence on the driving characteristics of the car. A wider tire width provides more driving stability and grip, but also higher rolling resistance. A higher tire height provides more comfort and driving feel, but also a lower top speed.

The tire size can be calculated with a simple formula:

• Tire diameter: 2 * tire width * tire height / 100
• Tire circumference: Tire diameter * Pi

The tire size consists of the following sizes, which you can find on the sidewall of the tire in a combination of numbers and letters, for example: 205/55 R 16 91 V.

• The tire width in millimeters (e.g., 205 mm) indicates how wide the tire is at its widest point. The width varies depending on the rim width on which the tire is mounted.
• The height-to-width ratio in percent (e.g., 55%) indicates how high the sidewall of the tire is in relation to its width.
• The construction type of the tire (e.g., R for radial) indicates how the carcass of the tire is constructed. Most modern passenger car tires are radial tires (R), in which the carcass threads run radially to the direction of travel.
• The rim diameter in inches (e.g., 16 inches, ca. 41 cm) indicates the diameter of the rim on which the tire can be mounted.
• The load capacity index or load index (e.g., 91) indicates the maximum weight the tire can carry.
• The speed index (e.g., V) indicates the maximum speed the tire can withstand.

PERMISSIBLE DEVIATIONS FROM THE TIRE SIZE

In some cases, deviations from the tire size specified in the vehicle registration document are also permitted. However, these deviations must be approved by an expert.

The permissible tire size for a car is specified in the vehicle registration document. The vehicle registration certificate also contains information on the maximum permissible speeds and axle loads.

The tire size must not be larger than the size specified in the vehicle registration document. This also applies to the tire width, tire height and tire diameter. However, the tire size may be smaller than the size specified in the vehicle registration document. In this case, however, the maximum permissible speed and the axle load must be reduced.

Permissible deviations from the tire size are:

• +/- 3% for the tire width
• +/- 5% for tire height
• +/- 2% for tire diameter

However, if you want to use other tire sizes, you have other options. In the so-called CoC document (Certificate of Conformity), which is part of the vehicle documents, you will find all wheel and tire combinations that are approved for your car under numbers 32 and 50. You do not have to have these entered in your vehicle documents as long as you have the CoC document with you.

Another option is to carry out a tested and certified conversion. In this case, you can have tire dimensions that deviate from the specifications in the vehicle documents fitted if they are approved by an expert and entered in the vehicle documents. However, you must bear in mind that further modifications to the vehicle may be required, such as to the bodywork or the brake system.

What are the advantages and disadvantages of different tire sizes?

The choice of tire size not only affects the appearance of the car, but also the driving behavior, fuel consumption and wear. There are various advantages and disadvantages to consider:

• Wider tires have a larger contact area and thus better grip on the road. This improves cornering stability and braking behavior. However, wider tires also have higher rolling resistance and thus higher fuel consumption. In addition, wider tires are more susceptible to aquaplaning and crosswinds.
• Flatter tires have a lower sidewall height and thus greater stiffness. This improves steering precision and handling. However, flatter tires are also less comfortable and generate more noise. Furthermore, flatter tires are more susceptible to damage from curbs or potholes.
• Larger rims have a larger diameter and thus lower ground clearance. This improves the appearance and aerodynamics of the car. However, larger rims also have a higher weight and thus higher fuel consumption. In addition, larger rims are pricier to purchase and maintain.

Table of tire size depending on the rim width

The following table shows the permissible tire sizes depending on the rim width:

Winter is just around the corner, and many drivers are wondering if they can keep their summer tires for a while longer.

Or whether they need to switch to winter tires. In this blog post, we explain what the law says, the risks of driving with summer tires in winter, and what penalties you can expect if you get caught.

WHAT DOES THE LAW SAY?

In Germany, there is no set date by which you must change your summer tires. Instead, there is what is known as a situational winter tire requirement.

This means that you are only allowed to drive with summer tires if the weather and road conditions allow it. If it is snowing, slippery or slushy, you must change to winter tires. This also applies to all-season or all-weather tires, which are only considered winter tires if they have the snowflake or alpine symbol on the tire sidewall.

WHICH VEHICLES NEED WINTER TIRES?

The situational winter tire requirement applies not only to passenger cars, but also to trucks, buses, motorcycles, and trailers. It also applies to foreign vehicles driving in Germany. The only exception is vintage cars with H license plates, which cannot be fitted with winter tires for technical reasons.

The winter tire obligation does not only apply from October to Easter, as is often assumed, but all year round. This means that you must change to winter tires even in summer when winter conditions prevail. Conversely, you can drive with summer tires in winter when it is dry and warm.

WHAT ARE THE RISKS?

Driving with summer tires in winter is not only illegal, but also dangerous. Summer tires are optimized for higher temperatures and dry roads. They have a harder rubber compound and a different tread design than winter tires. Therefore, they provide less grip and traction at low temperatures and on wet or slippery roads.

This negatively impacts the handling of the vehicle. For example, when braking with summer tires on snow or ice, the stopping distance is considerably longer. According to the ADAC, the stopping distance at 50 km/h can be up to 11 meters longer than with winter tires. That can make the difference between avoiding an accident and not.

Cornering and accelerating in winter is also more difficult with summer tires. The car can easily skid or lose control. This increases the risk of a collision or skid.

In addition, driving with summer tires in winter can lead to more wear and tear on the tires. The low temperatures cause the rubber to become brittle and crack. This shortens the life of the tires and can lead to tire failure.

WHAT ARE THE PENALTIES?

If you are caught driving with summer tires in the winter, you face several penalties. First, you can get a fine of at least 60 euros and a point in Flensburg. If you endanger others or cause an accident, the fine can increase up to 120 euros and two points.

On the other hand, you may also be partly to blame for an accident, even if you did not cause it yourself. This may mean that you have to pay part of the damage yourself, or that the insurance company reduces or refuses payment.

You may also be stopped by the police and asked to change to winter tires. If you do not comply with this request immediately, the police may ban you from driving or impound your car.

CONCLUSION

Driving with summer tires in winter is not a good idea. Not only is it illegal, but it’s also risky. You endanger yourself and others, and you may be fined.

Therefore, switch to winter tires as soon as weather and road conditions warrant. This will make your winter driving safer and more comfortable.