Does my Radiator really need a flush? This is a great question! We get it almost every day. The coolant does not have to deal with combustion gasses like engine oil does, but the additives do break down over time and lose its effectiveness. As time goes by, the additives for rust and corrosion tend to break down. You also start to lose the boiling point and freeze point protection. As rust and corrosion happens it sends particles and debris into the radiator and heater core. There they build up and start to affect the flow of coolant. This can cause an overheating of the engine or a lack of heat from the heater. Those particles are also like sand paper to moving parts like the water pump and thermostat. This can cause premature wear and failure. What does that mean to you ?? More Money More Money!
So how often should I flush the coolant? How is it done? Glad you asked! Your best place for information is your owners manual. But as a general rule every 2-3 years or 30000 miles is a good average. Keep in mind your owners manual recommendation is under best case driving conditions. We are in Texas and it is Hot and %&*#!?! and that is in December so it is always a good idea to get it checked with every other oil change or so. Some coolants like oils these days can go longer so do some research on your make and model. The manual and our recommendation is just a guide.
For a proper flush the coolant is drained. The radiator and engine block are then flushed to remove debris. This can be done manually, but most of the time is done with a flush machine. Then new coolant and water at the proper mix is added and the system is bled out to remove all air. We personally like to use a coolant additive from BG Products. It is a 2 part with a cleaner and an additive. The important part though is to have it checked and done on a regular basis!