Tire Rack offers a tire shaving service that has been primarily used for preparing tires for competition use. This same service is used to remove tread rubber from new pairs or street tires to allow them to match the remaining tread depth of the other partially worn tires that will remain on the vehicle. In addition to providing equivalent tread depth to eliminate driveline stress, shaved tires will better match the traction and handling qualities of the remaining worn tires. This service can be performed on a tire with a starting tread depth higher than 4/32".
While the cost of our street tire shaving service ranges between $25 and $35 for each tire, it is significantly less than the cost of unnecessarily replacing the remaining two or three good tires with lots of mileage still available from them. We can't accept tires at one of our locations to be shaved, they must be purchased from us and we'll ship the tire after shaving to you.
When it comes to tires for autocross and track use, the reason they're so effective is because they feature shallow tread depths and their contact patch acts as a single unit. Any tread design that breaks up the contact patch into smaller elements or adds more tread depth will increase the tread block squirm and reduce dry performance. Tires typically provide their worst wet traction and best dry performance just before they wear out. The heat generated every time a tire is driven activates bonding agents in the rubber. As this process repeats throughout the tire's life, its rubber compounds gradually harden and lose flexibility reducing the tire's grip. Therefore, a shaved new tire will provide more traction than a tire worn to the exact same tread depth after being driven for thousands of miles on the road.
Tire shaving is an effective means of permitting more of a tire's performance capability to be realized early in its life. In many cases, shaved tires used in competition actually have a longer useful life than tires that enter competition at full tread depth. A shaved tires's tread profile will usually result in a little more increase in the width of the tire's contact patch, putting a little more rubber on the road. The resulting shallower tread depths reduce the slip angle, increasing its responsiveness and cornering power by minimizing tread block squirm.
To gain a better insight into tire shaving, read "Shaving Tire for Autocross / Track Use / Competition."