Does extending oil drain intervals void new car warranties?
No. Automakers warrant cars against failures or malfunctions due to manufacturing defects for a period defined by time or mileage. No maintenance practice such as extending drain intervals, can render the warranty null and void. When a failure or malfunction occurs, the car dealer or a representative of the car maker will examine the failed or malfunctioning part to determine the cause of failure or malfunction. If an indisputable cause-and-effect relationship between the failure and the length of the oil drain intervals cannot be established, then the length of the oil drain intervals is immaterial to the warranty claim and the claim may not be refused on the basis of extended oil drain intervals. In fact, when AMSOIL Dealers notify AMSOIL INC. that car dealers or other businesses are misinforming their customers about warranty issues surrounding synthetic oils and extended drain intervals, AMSOIL INC. sends the following letter to the car dealer or business: It has come to our attent
