To properly protect your child, the car seat must be in good shape with all labels and instructions present and readable. Dorel Juvenile Group car seats now have expiration dates molded into the shell and sometimes the base of the car seat. The expiration date will be from 6 to 10 years after the manufacture date. Unless you know the history of a car seat, do not use it. Do not buy a second-hand car seat. For older car seats, the expiration date can be determined by adding 6 years (or 10 years for 3-in-1 seats) to the manufacture date stamped on a label on the seat.