Where to Find Your Tire Size
A tire’s sidewall contains standardized information divided into several key sections. Together, these markings describe the tire’s dimensions, construction, performance limits, and regulatory compliance.
Tire Specifications
This section describes the fundamental characteristics of your tire, including:
Tire size
Construction type
Load rating
Speed rating
These elements define how the tire is designed to fit and perform on a vehicle. Understanding these markings is essential when selecting replacement tires and is part of reading standardized tire markings.
Department of Transportation (DOT) Safety Code
The DOT marking confirms that the tire complies with applicable safety standards. Following the DOT symbol is the Tire Identification Number (TIN), which provides manufacturing details.
The first characters identify the manufacturer and production plant. The last four digits indicate the week and year of manufacture
This information helps identify when the tire was produced, though tread wear remains the primary indicator for replacement.
UTQG Code
The Uniform Tire Quality Grading (UTQG) system was established by the National Highway Traffic Safety Administration (NHTSA). It grades tires based on government-prescribed test methods across three criteria:
Treadwear: Indicates the relative wear rate of the tire within a manufacturer’s lineup
Traction: Grades (AA, A, B, C) reflecting the tire’s ability to stop on wet pavement
Temperature: Grades (A, B, C) indicating the tire’s resistance to heat buildup
Tires graded below C for traction or temperature are considered unacceptable for road use.
Icons and Symbols
Some tires feature icons or letters that indicate specific characteristics or intended use.
M+S (Mud and Snow) markings identify tires designed for use in mud and snow conditions. These markings are commonly found on all-season tires
Additional symbols may appear depending on tire type and application.
Finding Tire Size in Your Vehicle Owner’s Manual or on Your Door
Your vehicle manufacturer specifies the recommended tire size and specifications for your vehicle. This information can typically be found in the vehicle owner’s manual (often stored in the glove compartment), or on the tire information placard located on the driver’s side door or door pillar
These sources also list the recommended inflation pressure for your vehicle. For a detailed explanation of sidewall markings, refer to the section above on finding your tire size on your tire.
What Are OE Tires?
OE stands for Original Equipment, meaning the tires were approved by the vehicle manufacturer to be fitted to the vehicle at the time of production.
Some manufacturers, such as Audi, BMW, Mercedes, and others, equip their vehicles with tires developed specifically for their models. These tires carry a manufacturer-specific OE marking on the sidewall.
When replacing these tires, Michelin recommends fitting tires with the same approved OE marking to help maintain the vehicle’s intended handling, comfort, and performance characteristics, including respecting tire load and speed ratings.
Common OE Markings by Vehicle Brand
★ = BMW, MINI
MO = Mercedes-Benz
MO1 = Mercedes-AMG
AO = Audi
RO1 = Audi quattro
VO = Volkswagen
N0, N1, N2, N3, N4 = Porsche
These markings indicate that the tire was developed and approved for a specific manufacturer or vehicle model.
FAQ
How to Read and Understand Tire Size
The correct tire size can be found on the tire sidewall, in the vehicle owner’s manual, or on the tire information placard located on the driver’s side door or door pillar.
Tire size recommendations are defined by the vehicle manufacturer to ensure proper fitment and performance. Choosing a different size may affect handling, clearance, and safety, and should only be done with guidance from a trained tire professional.
No. Tires with the same size may have different load ratings, speed ratings, or construction features. It is important to ensure that replacement tires meet all manufacturer-specified requirements, not just the size.
An OE (Original Equipment) marking indicates that a tire was developed and approved for a specific vehicle manufacturer or model. When present, Michelin recommends replacing tires with the same OE marking to maintain the vehicle’s intended performance.
No. The DOT date code indicates when a tire was manufactured, not its size. Tire size selection should be based on the markings specified by the vehicle manufacturer and listed on the tire sidewall or vehicle placard.
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