Aftermarket parts are made by someone other than the original equipment manufacturer. In our experience with Toyota vehicles, NO one makes an aftermarket part that matches O.E. quality. Most independent shops use aftermarket parts extensively as they cost considerably less and offer a better profit margin. As I'm writing this we currently have a Lexus IS300 in the shop for an engine replacement. The oil change facility that last worked on it used a cheap aftermarket oil filter and six months later the gasket that seals it to the engine block failed. Within seconds all the oil in the engine was pumped out past that failed gasket, the engine suffered extensive damage. The facility refused to help out the customer as they only warranty their work for three months. Not to say we haven't had to warranty a Toyota part from time to time but it's rare and they warranty their parts for one year, unlimited miles. We do occasionally use aftermarket parts with our customer's approval, radiators and catalytic converters for example, because of the large difference in price. Koyo radiators are very well built, offer a lifetime part warranty and cost considerably less than a Toyota unit. Aftermarket catalytic converters are not even close to Toyota in quality but the price difference can be so great that it makes a good option. In general though, we highly recommend using only Toyota or O.E. parts on your vehicle.
