My winter goal is to get my ac working properly again. I need to change the expansion valve and dryer. I have read in several places that Four Seasons was the OEM for the expansion valve. I know that OEM is important for this part as aftermarket pieces can vary greatly in the pressures they work on. Does anyone know if Four Seasons is really the proper OEM manufacturer? I'm asking because the prices for this part varies from $30 to almost$200. There is no reason for an expansion valve to cost anywhere NEAR $200.