On most cars, the tires on all four corners are the same size. They have the same width, aspect ratio, and diameter. However, this is not true of all vehicles. Case in point the new Volkswagen ID.4, which has trims in which the front and rear tires are not the same. This is often called "staggered" tire sizes. What makes the ID.4 unusual is that it is not a performance vehicle.
Automakers have long opted to use different tire sizes, front and rear, so that the driven wheels are a bit more capable of handling the traction and torque demands of its two-wheel-drive powertrain. On performance cars, this has made some sense. The vehicle ends up being a bit more balanced in its handling when driven near its limits.
What is changing is that electric vehicles now offer tremendous torque. Much more than modern conventionally-powered vehicles. Combine this with two-wheel drive, and the results are that the vehicle can be a bit unbalanced in certain circumstances. To help manage this, automakers may adopt differing tire sizes, front and rear.
This is all fine until the first time a tire rotation is scheduled or required. When the time comes, the tires can only be swapped from side to side, not also front to rear. This limits the options one has for tire rotation but is not a big deal. Particularly since with most performance vehicles, the expectation is that tires are not going to last as long as on a conventional car anyway.
The difficulty to avoid is a replacement tire that has a directional tread design. One of the most popular tires today is the Michelin CrossClimate2. This all-weather tire is, at its core, an all-season tire, but it does have a 3-Peak-Mountain-Snowflake stamp signifying it is capable of severe snow duty. For this reason, and many others, it is a very popular tire for folks to adopt when it comes time for the first tire replacement of the vehicle’s life.
The potential problem is that this tire has a directional tread design. It can only roll one way (except when backing up at slow speeds, of course). What this means is that the tires can only be rotated from front to rear. Specifically not back to front. Do you see where this is headed?
On a vehicle in which the tires are staggered in size front to rear, the only option for rotation is side to side. If you mistakenly purchase directional tires for such a vehicle, they can never be rotated. This will minimize your treadwear and will shorten the life of the tire dramatically.
If you have any tire tips, please place them in the comments below. We are always interested in new tire topics to explore.
Image of Michelin CrossClimate2 tire by John Goreham.
John Goreham is a long-time New England Motor Press Association member and recovering engineer. John's interest in EVs goes back to 1990 when he designed the thermal control system for an EV battery as part of an academic team. After earning his mechanical engineering degree, John completed a marketing program at Northeastern University and worked with automotive component manufacturers, in the semiconductor industry, and in biotech. In addition to Torque News, John's work has appeared in print in dozens of American news outlets and he provides reviews to many vehicle shopping sites. You can follow John on TikTok @ToknCars, on Twitter, and view his credentials at Linkedin
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