The average lifespan of a BMW 335i can vary depending on factors such as maintenance, driving habits, and environmental conditions. With proper maintenance and care, a BMW 335i can last well over 100,000 miles. However, some owners have reported issues with high-pressure fuel pump failure, water pump failure, and turbocharger failure around the 80,000-mile mark. It is important to stay up to date on regular maintenance to maximize the lifespan of your BMW 335i.