Tire Codes – What Do They Mean?

Tire Codes - What Do They Mean?







Tire Codes – What Do They Mean?

Tire Codes – What Do They Mean?  There’s a lot of important information on the sidewall of a tire, but deciphering all of it can be tough.  By understanding these codes, you can decide if a tire is right for their vehicle, driving style, and road conditions.  According to US News & World Reports, some of the information is mandated by government regulation, providing a description of the tire’s size, intended use, capacities, and manufacturing source.

Brand and Model

The largest type on the sidewall shows its brand and model. That might seem like basic information, but if you are shopping for a used car, you’ll want to walk all the way around to make sure that all of the tires match.  If you are replacing your vehicle’s tires, consult your car’s owner’s manual to determine its minimum tire specifications. Don’t rely on the numbers on the existing tires, as those tires may be replacements that don’t match the vehicle’s needs.

Width of the Tire

If there are letters, they’re likely a P that indicates that it is a passenger car tire or LT to signal it is a light truck tire. The first three-digit number is the tire width in millimeters measured at its widest part, not the tread.  High-performance car tires tend to have higher section width than more mainstream vehicles.

Height of the Tire’s Sidewall

The two-digit number following the slash in the tire size description is the tire’s aspect ratio, the sidewall height expressed as a percentage of the tire’s width. If the markings say 255/55R18, it means that the height of the sidewall is 255 multiplied by .55, or 140 millimeters.  The higher the aspect ratio, the taller the sidewall is in relation to the tread width. If it is a low number, it means that it is a low-profile tire such as those found on higher-performance cars.   Passenger vehicles equipped with tires featuring higher aspect ratios generally have a softer ride than models with low-profile tires.

Size of the Wheel It Fits

The next part of the tire size is a letter denoting its construction, sometimes a Z speed rating, and the size of the wheel that it is designed to fit, measured in inches. When it says R18, it means that it has a radial-ply construction and it fits an 18-inch rim.  A tire can only be installed on a wheel that is identical to its inner diameter.

Maximum Load the Tire Can Carry

The next set of letters and numbers are a tire’s service description, which tells you its load index, or how much weight it is designed to carry.   You can find the recommended tire load range for your vehicle by looking at the tire placard on the pillar behind the driver’s door or the vehicle’s owner’s manual.

Speed Rating

The final letter in the service description is the tire’s speed rating, or the maximum speed it is certified to safely be driven at when properly inflated and maintained. Speed ratings range from L (75 mph) to Y (186 mph).  When you are replacing tires, the new tire’s speed rating should match or exceed the value listed in the vehicle’s owner’s manual.

Tire’s Birthdate

Elsewhere on the tire there will be a block of numbers and letters known as a DOT Code (Department of Transportation Code). The first part is a batch and plant identifier that can help you in the case of a recall, but it is the last four digits that are more important.  The final four numbers show the date that the tire was manufactured. The first two digits are the week and the second two are the year.  It’s especially important to look at the date if you are considering a used car or your car gets limited use each year.  While tires don’t have an expiration date, tires older than five years should be carefully inspected, after 10 years they should definitely be replaced.

Maximum Inflation Rating

Another number you will find on the tire is its maximum inflation pressure. It is not, however, the pressure that you want to inflate your tires to. Instead, you should consult your car’s owner’s manual or tire placard for the recommended tire pressure.  Inflating your tires to maximum pressure will create uneven tire wear, change the car’s handling and comfort, and potentially compromise its stability control and advanced safety systems.

Uniform Tire Quality Grading / Treadwear

The Uniform Tire Quality Grading (UTQG) marking is designed to show a tire’s treadwear rating, temperature range, and traction ability.  The treadwear test uses a reference tire with a rating of 100 as a baseline. A tire with a rating of 300 would be expected to last three times as long. A tire with a treadwear rating of 640 could be expected to last 6.4 times longer than the reference tire.


Uniform Tire Quality Grading / Temperature and Traction

Temperature ratings are a measure of a tire’s propensity to create heat and its ability to dissipate it. A rating of “A” is the best and “C” is the lowest. All tires sold in the U.S. must earn at least a “C” grade.  A tire’s traction grade measures its coefficient of friction or braking g force as it is forced to skid across wet concrete and asphalt surfaces. A score of “AA” is the best a tire can earn, while a “C” is the lowest. The test does not evaluate a tire’s tread design or its ability to resist hydroplaning.

Drive AutoCare doesn’t sell tires but we highly recommend Discount Tire Company in Encinitas and Discount Tire Company in Escondido.



German Automobile Repair Tips

German Automobile Repair Tips

German Automobile Repair Tips

German Automobile Repair Tips from DRIVE AutoCare where we specialize in Mercedes Benz, BMW, Porsche, Audi, Volkswagen and Mini Cooper. Since the 1980, we have learned a lot about German-made vehicles:

1. German automobiles require specialized service:  German manufactured vehicles are specialized for performance.  To ensure performance, specialty tools and expensive diagnostic equipment are required that are specific to your make, model and brand. It is strongly recommend that you stay away from generic automotive shops that work on all makes and models and do not have the equipment, or expertise to properly maintain and repair your German performance vehicle.

2. Your vehicle has upwards of 90 computers on board: Today’s complex German vehicles are rolling electronics and computers. Today’s Mercedes Benz, Audi, Porsche, BMW, Mini or Volkswagen often have thirty (30) or more on-board computers and control modules with some models having upwards of ninety (90) electronic control units. These modules require specialize diagnostic equipment to conduct repairs, replace and program appropriately for your vehicle.  Everything from braking systems, steering, throttle, transmission and engine management are all interconnected on a common communication bus within your vehicle. Periodically, these modules should be checked for any faults or anomalies and update their programming as per the manufacturer service bulletins.

3. When is service due? Whether you drive a late model Mercedes Benz, BMW, Porsche, Audi, Volkswagen or Mini Cooper, your car is programmed to notify you when it believes that conditional service is due. Depending on your specific make and model this includes, engine oil service, cabin micro air filter, engine air filter, brake fluid, brake pads and even your annual state emissions test.

Specialized factory diagnostic equipment is required to read conditional service intervals and to reset them after the service is performed.  Keep in mind that dealers want to sell you a new car at 50,000 mile, the “free” prepaid maintenance is not a free as it may appear. You should schedule an oil service every 5,000 miles for turbo and supercharged engines like the 1.8T, 2.0T in VW and Audi and every 7,500 for all other late models. TDI diesel engines require specific engine oil that should not be mixed.  Older models using mineral based oil should not use full synthetic oil. Always follow the manufacturer recommendation for oil viscosity or consult our Service Manager. Other than vehicles with mechanical lifter designs, such as the BMW M-series which requires 60-weight oil, and TDI diesel engines, Mobil 1 0W/40 engine oil is best for most German manufactured makes and later models.

4. My transmission is not shifting right – is it my tires.  Mercedes Benz, BMW, Audi, Porsche, Volkswagen and Mini all use limited slip differentials. Whether you are driving an Audi A6 Quattro or a Porsche 4S, your tires must be matched in circumference. A 2 cm (or 2/32 inch tread depth) difference between tires on the same axle can cause rotational speed variances that will cause havoc with today’s drive train management systems.  You should never use mismatched tires on the same axle and on the 4-wheel drive systems such as the Audi Quattro; all 4 must be circumference matched within 2cm. Remember tire wear will affect the circumference of a tire, so they should be of the same age. It is recommended tires on the same axle be replaced at the same time and in the case of the Quattro systems, all four tires.

5. Spongy brake pedal. Brake fluid attracts moisture. You should change your vehicle’s brake fluid every two-years. Most late model vehicles will have a conditional service reminder set.

6. Breathing clean air. Most German manufactures recommend replacing the cabin micro air filter every 40,000 miles. Do not forget these filters as they filter the air that you breathe. Additionally, a clogged or dirty filter will cause the blower motor to work harder and can cause damage to the motor and to the blow motor resistor.

7. Prevent interior flood damage. If your Mercedes Benz, BMW, Audi, Porsche, Volkswagen or Mini has a sunroof, take the time to ensure the drains are cleaned. All sunroofs have a series of drains running forward and rearward from the sunroof through the vehicle body and out underneath the vehicle. If this gets clogged with dirt or debris, water will back up flooding the interior of the vehicle. Your vehicle has sensitive electronics under your seats that do not survive under water leading to costly repairs.

8. Have a spare key. You should always have a spare key for your German vehicle. Electronic keys die leaving the vehicle immobilized and you stranded. All later model Mercedes Benz, BMW, Audi, Porsche, Mini and Volkswagens have security chips that marry the key to the car, these can not be tampered with and once a key dies your vehicle will be immobilized and unmovable.


For more information, please see our website:  www.driveautocare.com.



Digital Vehicle Inspections – Seeing Is Believing

Digital Vehicle Inspections - Seeing Is Believing









Digital Vehicle Inspections

Digital Vehicle Inspections:  DRIVE AutoCare now employs the latest digital technology which allows our customers to see, before buying.  A picture is worth a thousand words so in to help our customers visualize the necessity of recommended services, DRIVE AutoCare is taking multiple photos of the vehicle conditions to illustrate the metal-to-metal brakes, fluid leaks, or bulging tires and how any of these or other service scenarios can be remedied.  Industry best practices suggest that our technicians take between five and seven photos during every inspection. Think of the multi-point inspection feature as your gateway to an illustrative story detailing your vehicle’s overall condition.

These inspections are color-coded, providing sections for technician notes and recommendations. The Notes section is the go-to place for illustrating problems and the Recommendations area is the place to offer vehicle fixes, including educational videos.  The digitally completed forms describe the condition of everything from brakes to suspension, alignment, tires and more, using easy-to-understand color coding. Green means good, yellow is for instances where repairs may be needed soon and red is for issues warranting a fix now.

DRIVE AutoCare offers these inspections free of charge on every vehicle.  Once completed, the inspections are emailed or texted to the client by our Service Manager.  Make an appointment on our website, www.driveautocare.com.


Free Car Battery Check

Free Car Battery check


A Free Car Battery Check today at DRIVE AutoCare can keep the tow truck away.  That’s why we suggest you come in for a free, digital battery inspection at any of our three locations.  It only takes a few minutes and, if needed, we can replace the battery while you wait.  No appointment necessary!!!

It’s a fact that car batteries don’t last forever and they will eventually need to be replaced.  Assuming ideal conditions (moderate climate with no excessive humidity), you can expect your car battery to last about six years.  But in reality, a car battery only lasts between two and five years. Excessive heat and overcharging are the two main reasons for shortened battery life.  Excessive heat causes the battery fluid to evaporate, thus damaging the internal structure of the battery. A malfunctioning component in the charging system, usually the voltage regulator, allows too high of a charging rate, leading to slow death for a battery.  In colder temperatures, the thickness of the engine oil increases making the engine harder to turn over so the battery has to work harder, to start your engine.

To get the most life out of a battery, the Car Care Council suggests the following:

  • Be sure the electrical system is charging at the correct rate; overcharging can damage a battery as quickly as undercharging.
  • Always replace a battery with one that’s rated at least as high as the one originally specified.
  • Keep the top of the battery clean. Dirt becomes a conductor, which drains battery power. Further, as corrosion accumulates on battery terminals it becomes an insulator, inhibiting current flow.

Independent Mercedes Repair

Independent Mercedes Repair

Independent Mercedes Repair

Independent Mercedes Repair and maintenance means not going to the dealer.  If you want to save time and money, DRIVE AutoCare in Solana Beach, Del Mar, Rancho Santa Fe, Cardiff and Encinitas is an ideal option to the Mercedes-Benz dealer.

Vehicle Longevity

One of the best reasons to turn to DRIVE AutoCare is our dedication to the long life of your vehicle.  A dealership makes most of its money on the sale of new cars.  As an independent repair shop, we are focused on making sure your vehicle remains in good operating condition for a long period of time.

Lower Prices

A dealership uses expensive parts manufactured by the car company. Typically the dealer promotes these as the best parts.  However, many parts obtained from other sources are just as good without the inflated price.  Only an independent Mercedes repair shop can access these non-dealer parts which can keep your costs down without any sacrifice of quality.  And the misconception that non-dealer parts void your warranty is absolutely false.

Personal Attention

A dealer handles large numbers of customers on a daily basis (you’ve experienced the lines).  When you take your vehicle to an independent Mercedes repair shop like ours, you know you can talk to someone who remembers you and your car (and your dog and your kids).  We offer a customer shuttle and complimentary Concierge Service (we pick up your car, repair it and return it to your home or office).

More Convenient

As an independent shop, DRIVE AutoCare offers more flexible hours, as well as a number of other conveniences to make things easier for our customers. Some of these services include early and late pickup and drop off, loaner cars, vehicle delivery and pickup, online appointment making and shuttle services. And we are located in a residential area providing easier access to our locations.


When faced with choosing between an independent repair shop and a Mercedes-Benz dealership, you may feel as if the dealership is the better choice. However, you can save time and money by choosing DRIVE AutoCare without concern over sacrificing the quality of the service.

Summer's End Is The Perfect Time For Car Care

Summer’s End Is The Perfect Time For Car Care

Summer’s End Is The Perfect Time For Car Care

Summer’s end is a perfect time for car care to assure you and your family of worry-free driving this fall and winter.

The vacations are over and the kids are going back to school. The National Institute for Automotive Service Excellence (ASE) suggests you take advantage of this lull to prepare your vehicle for the seasons ahead.  Breakdowns are never convenient and the following tips from ASE should give parents and students a preventative maintenance road map:

Recommended Service Schedules

We suggest you follow the manufacturer’s recommended service schedules which can be found in your owner’s manual.  Or contact one of DRIVE AutoCare‘s Service Managers who have complete access to this information.

Engine Performance

Have engine problems (hard starts, rough idling, stalling, diminished power, etc.) corrected soon as colder weather will make the existing problems much worse.  We also recommend you replace any dirty filters (air, fuel, PCV, etc.)


If you are planning on driving to the mountains this winter, we suggest you put a bottle of fuel de-icer in your tank monthly to help keep moisture from freezing the fuel line.  Also, refuel at half a tank  to prevent moisture from forming in the first place.


Change your oil and oil filter as specified in your manual more often (every 3,000 miles or so).

Cooling System

The cooling system should be flushed and refilled as recommended. The level, condition, and concentration of the coolant should be checked periodically.  The tightness and condition of belts, clamps, and hoses should be also be checked.


The heater and defroster must be in good working condition for passenger comfort and driver visibility.

Windshield Wipers

Replace old blades and stock up on windshield washer solvent… you’ll be surprised how much you use.


Stop by DRIVE AutoCare for a battery test, it’s only accurate way to detect a weak battery is with professional equipment.  We also suggest you have corrosion removed from posts and cable connections and all surfaces.


Inspect all lights and bulbs; replace burned out bulbs; periodically clean road grime from all lenses with a moistened cloth or towel. If your lenses are yellowed, we can professionally restore them.

Exhaust System

Exhaust fumes can be deadly.  Have your vehicle placed on a lift and the exhaust system examined for leaks;  the trunk and floorboards should be inspected for small holes.


Worn tires will be of little use in winter weather. Examine tires for remaining tread life, uneven wearing, and cupping; check the sidewalls for cuts and nicks. Check tire pressure once a month,and rotate as recommended:   Discount Tire Company will do it for free. Don’t forget your spare and be sure the jack is in good condition.

Emergency Equipment

Carry blankets, flares, flashlight and a few “high-energy” snacks.


Check Engine Light Rancho Santa Fe Solana Beach Del Mar Encinitas

Check Engine Light Rancho Santa Fe Solana Beach Del Mar Encinitas

Check Engine Light Rancho Santa Fe Solana Beach Del Mar Encinitas

The Check Engine Light Rancho Santa Fe Solana Beach Del Mar Encinitas, according to Consumer Reports, is the most misunderstood indicator on your dashboard.  This warning light means many different things, from a loose gas cap to a seriously misfiring engine.  While you don’t have to pull the car over immediately, you should get the car checked out as soon as possible.  By ignoring the warning you might seriously damage expensive components.  Additionally, this light is a sign that your car is getting poor mileage and emitting higher pollutant levels.  The check engine light is part of your car’s on-board diagnostics (OBD) system. When there’s a problem that the system can’t correct, the computer illuminates a yellow warning indicator  and simultaneously stores a “trouble code” in its memory to identifies the source of the problem when scanned by a service technician.

In 1996, under OBD II regulations, car manufacturers were required to install a much more sophisticated system that essentially acts like a built-in emissions testing station. The computer monitors and adjusts dozens of components and processes. For example, it continually samples exhaust emissions as they leave the engine and again as they leave the catalytic converter (a device that removes pollutants from the exhaust). The system also monitors the fuel system to ensure gasoline vapors are not escaping into the atmosphere. If a problem occurs, the computer will wait to see if it corrects itself before turning on the light.

What To Do?

When the check engine light illuminates, it will either blink or remain constant, depending on the problem. Either way, you should have the vehicle checked, although a blinking light or a red light indicates a problem that needs immediate attention. In late-model cars, a blinking light usually indicates an engine misfire so severe that unburned fuel is being dumped into the exhaust system, where it can quickly damage the catalytic converter, requiring an expensive repair. If that happens, you should reduce power and have the vehicle looked at as soon as possible. If the light is steady, the problem is not an emergency but you should schedule an appointment as soon as possible.

Smog Inspections

Finally, when the check engine light comes on, do not go for a smog inspection. An illuminated warning light is an automatic failure, even if the problem is nothing more than a loose gas cap. And don’t bother trying to fool the inspection station by disconnecting the battery or using any other method to erase the trouble code. Your vehicle’s computer will let the inspection station know that its codes have been erased, and you’ll just have to go back again.



Summer Road Trip Checklist

Summer Road Trip Checklist

Summer Road Trip Checklist

Summer Road Trip Checklist: AAA reports that 4 of 10 drivers are unprepared for vehicle breakdowns which can take the joy out of your trip.  The Car Care Council recommends taking the following steps before you leave home:

  • Check the battery:  Be sure the electrical system is charging at the correct rate; overcharging can damage a battery as quickly as undercharging.  Excessive heat and overcharging shortens the life of a battery.  Replacing an old battery is an inexpensive insurance policy.
  • Check the tires:  Be sure to check the tire pressure and tread including the spare. Uneven wear indicates a need for wheel alignment. Tires should also be checked for bulges and bald spots.
  • Check the air conditioning:  Proper cooling performance is critical for interior comfort.
  • Check all fluids:  Check the engine oil, power steering, brake and transmission as well as windshield washer solvent and antifreeze/coolant.
  • Check the wipers and lighting:  Check that all interior and exterior lighting is working properly and replace worn wiper blades so you can see clearly when driving during precipitation.
  • Check the emergency kit:  Purchase one if you don’t have one or restock, if necessary.

DRIVE AutoCare also recommends inspecting the brake system and performing a tune-up to help the engine deliver the best balance of power and fuel economy.



Auto Repair Headlights Solana Beach Del Mar Rancho Santa Fe

Auto Repair Headlights Solana Beach Del Mar Rancho Santa FeAuto Repair Headlights Solana Beach Del Mar Rancho Santa Fe

Auto Repair Headlights Solana Beach Del Mar Rancho Santa Fe

Auto Repair Headlights Solana Beach Del Mar Rancho Santa Fe, we recommend replacing headlights in pairs and restoring your lenses as needed.  Replacing just one failed bulb can result in an unbalanced or unpredictable headlight beam which is a potential safety risk.  For the driver, unbalanced headlights means the road ahead will not be properly lit.  For the oncoming driver, it will be harder to see and more difficult to position on the road; he may also be confused with a single headlight vehicle such as a motorcycle.

Many drivers will only replace a bulb that has completely failed, but for maximum driving safety, an aging bulb should replaced before it burns out. As the filament of a halogen headlight bulb ages, the bulb’s light output deteriorates. At the end of their typical service life, headlight bulbs project less light, reducing the driver’s nighttime visibility.  A new headlight bulb that typically projects a 240-foot beam will only be able to deliver a 160-foot beam after three years. That’s a whopping 33% percent less light and a critical safety concern.

Regarding headlight restoration,  the plastic components can yellow and haze with weather, sun and sand, limiting visibility and diminishing the appearance and value of the vehicle.  The dangers in terms of limited visibility are clear as it’s a factor in 2.8 million accidents, 23,000 fatal crashes and 2,300 pedestrian deaths each year (according to the Motor Vehicle Lighting Council). Dim headlight bulbs and hazy plastic headlight lenses or surfaces may lead to this reduced visibility, putting you, your passengers and other cars at risk. The AAIA Car Care Council found that 26 percent of the cars it inspected had issues with their lighting system. Millions of cars on the road today have plastic headlight lenses. The problem increases with the age of the lens, and with the average age of cars on the road about 10 years old, the problem is growing. That is why it is important to correct hazy, dull headlights.


Rancho Santa Fe Mobil Gas Station and Automotive Repair

Rancho Santa Fe Mobil Gas Station and Automotive Repair

Rancho Santa Fe Mobil Gas Station and Automotive Repair

Rancho Santa Fe Mobil Gas Station and Automotive Repair will be replaced by the newly approved Gateway project in the Rancho Santa Fe village, a 2-story, 27,017-square- foot mixed-use building.

Residents of Rancho Santa Fe and Fairbanks Ranch should be aware that DRIVE AutoCare offers complimentary Concierge Service.  We will pickup your vehicle, make the necessary repairs, and return the vehicle to your home or office — all at no additional cost.  DRIVE AutoCare enhances automotive value, comfort & safety.  Forevermore, we will be obsessive in our quest to exceed the expectations of our community with trustworthy advice and legendary service.

The Gateway project will not have a gas station or an auto repair facility.  It will have a 5,000-square-foot market, more village parking with a three-level, 138-space underground garage, and a more “deserving” entry to the village from the south with a portion of the property preserved as green open space.   According to Robert Green, the retired building commissioner still serving in an advisory role to Rancho Santa Fe, the project “stacks up,” with 13 percent courtyards and 35 percent of the ground floor as leasable market space.

DRIVE AutoCare has 2 locations in Solana Beach, easily accessible to Rancho Santa Fe:  128 N. Cedros Ave (858-793-0560) and 371 N. Highway 101 (858-755-5015).  Online appointments are available at www.driveautocare.com.  DRIVE repairs and maintains foreign, domestic and exotic vehicles.




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