Performance Products stocks thermostats for most Mercedes models 1972-on. A stuck or faulty thermostat can cause a myriad of cooling problems, including over-heating. Typically, this can be recognized if the coolant temperature gauge stays in the red zone but the radiator remains cooler to the touch. Also, a thermostat can be stuck open after the coolant has cooled off. Then the engine may not reach normal operating temperature and the heater performance is decreased. We also have thermostat housings, covers, gaskets and seals available for most models.