Carseat experation

Our carseat doesn't have an experation date but it does have an manufacturer date of Nov 2014 listed on it. My question is do all carseats expire after 6 years? We bought the carseat in 2015 for our son, have used it for our daughter and want to use it for this baby too. It's never been in an accident or any type of collision. So I still assume it's safe since its within the 6 year range until November 2020. tried to google this but I wasnt getting a straight forward reaponse... TIA.