How to Read Your Tires

Whether you drive a BMW, Porsche, Mercedes-Benz, Audi or Volkswagen, your vehicle’s suspension is designed to work with your tires to provide maximum road grip in a variety of conditions. To achieve maximum grip, your tires must be in good condition, properly selected and properly aired.

There are several things that you should know about the tires on your BMW, Porsche, Mercedes Benz, Audi or Volkswagen.

Proper Tire Inflation: Tires should be inflated not based on what is stamped on the tire, but what is specified for your specific vehicle and usage. Please consult your owner’s manual or check the sticker, often located behind the gas filler or on the driver door frame. A tire that is under inflated will wear prematurely on the outer edges, while a tire that is over inflated will wear in the center.

Speed Rating: In Germany, some highways do not have speed limits and as such speeds are higher than on most roads here at home. Your vehicle’s performance capacity dictates the speed rating you should have on your tires. Most commonly we see ratings of SR–112 mph, HR–130 mph and VR–in excess of 130 mph. When selecting new tires, be sure to match the appropriate speed rating for your BMW, Porsche, Mercedes Benz, Audi or Volkswagen.

Proper Size:  When selecting replacement tires for your BMW, Porsche, Mercedes Benz, Audi or Volkswagen, you typically will have several size options specified by the manufacturer that may be used. For example, a tire is sized by the width and the sidewall height followed by the speed rating and the wheel diameter it is designed for. Example: a 225/50VR16 tire has a sectional width of 225mm and aspect ratio of 50mm, is rated for 130+ mph and is for a 16 in rim.

Tire Age:  The age of your tire is stamped on the tire itself. You will find a four digit code that indicates the month and year of production. Most tire stores will not touch a tire that is more than 10 years old. For example, a tire stamped 0210 was manufactured the second month (February) of 2010.

Tire Wear: Tire wear is impacted by many factors including tire pressure, alignment and suspension. Some common wear patterns are as follows:

Center Worn – indicative of over inflation
Outer and Inner Wear – indicative of under inflation
Cupping or Scalloping – indicative of shocks being worn or springs too strong, permitting tire hop

Alignment (Toe, Camber, Caster) is critical to overall performance and tire wear. Alignment that is off may cause excessive wear across the face of a tire, inside edge only or outside edge only.  Please see the information posted at for more information on suspension geometry and alignments.

Whether you need service on your Mercedes, Porsche, Mercedes Benz, BMW, Volkswagen or Audi, proper maintenance can assure that today’s German performance vehicles will serve you for many miles and years to come. Seek Porsche, Mercedes Benz, Audi, Volkswagen and BMW service in Austin to ensure your German vehicle is running properly on the road—visit us at German Auto Center and we will be happy to assist you!