{"id":444620,"date":"2026-08-28T11:24:03","date_gmt":"2026-08-28T09:24:03","guid":{"rendered":"https:\/\/transfercasepartshop.com\/?post_type=tudastar&p=444620"},"modified":"2026-08-28T11:25:08","modified_gmt":"2026-08-28T09:25:08","slug":"homologated-tires-and-the-transfer-case","status":"publish","type":"tudastar","link":"https:\/\/transfercasepartshop.com\/en\/tudastar\/homologated-tires-and-the-transfer-case\/","title":{"rendered":"Homologated Tires and the Transfer Case"},"content":{"rendered":"

Why Tire Choice Matters on AWD Vehicles<\/strong><\/h2>
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Matching tire size on paper isn’t enough<\/h2>

Many drivers assume that as long as all four tires<\/a> match the size listed on the registration or the door placard, an all-wheel-drive vehicle will run fine. In reality, two tires with identical size markings can still have different actual rolling circumferences, sidewall stiffness, and load behavior, depending on the brand, tread pattern, and even production batch. On a conventional two-wheel-drive car, this difference is barely noticeable. On an electronically controlled AWD system, it can lead to serious, expensive damage.<\/p>

What does “homologated tire” mean?<\/h2>

A homologated tire \u2014 sometimes called an OE-approved or manufacturer-approved tire \u2014 is developed or tuned by the tire maker together with a specific car manufacturer for that model. The tuning process covers not just nominal size but the actual rolling circumference, sidewall and belt construction, grip and braking behavior, and how the tire interacts with ABS, stability control, and the AWD system. Approved tires often carry a special sidewall marking, such as BMW’s star (\u2605), Mercedes-Benz’s MO, Audi’s AO, Porsche’s various N-codes, or Land Rover\/Jaguar’s LR\/J marking.<\/p>

It’s worth distinguishing between mandatory type-approval for road use and manufacturer-specific homologation: a tire can be perfectly street-legal without carrying a particular carmaker’s own approval.<\/p>

How mismatched tires overload the transfer case<\/h2>

The transfer case distributes drive torque between the front and rear axles, typically through an electronically controlled, multi-plate clutch. The system continuously monitors wheel speeds, steering angle, and acceleration data, and can interpret a sustained speed difference between axles as loss of traction.<\/p>

If tires with different actual rolling circumferences \u2014 or unevenly worn tires \u2014 create a constant speed difference between axles even while driving straight, the transfer case keeps trying to “correct” a slip that isn’t actually there. Over time this causes:<\/p>