How many tires should be replaced at once for a BMW 3 Series?

[OJonathan]

Replace according to the actual situation. Replace the severely worn or damaged tire. If all tires have exceeded their service life, replace them all. Tire service life: Under normal driving conditions, the lifespan of a tire is generally 60,000-80,000 kilometers, approximately 3-5 years. It can be calculated from the production date (marked on the side of the tire), and the aging replacement cycle is five years. If it exceeds five years, the tire should be replaced even if the tread wear does not reach the limit. Methods to determine tire wear: There are mainly two types of markings on a tire that help the owner determine the wear condition. One is the rectangular raised mark located at the bottom of the tread groove, usually used to judge the degree of tire wear, and the other is the triangular mark located on the shoulder on both sides of the tire, which clearly indicates the position of the wear indicator. The thickness of the tire wear indicator is about 1.6 millimeters, which is the legal minimum groove depth. When the tire wears to this mark, the owner should replace the tire immediately.