Coolant Change
What is a coolant change or flush?
A coolant change involves simply draining the coolant at the bottom of the radiator, then topping up the radiator with fresh fluid until it it’s full. Alternatively, the technician can remove the drain plugs on the engine block, which lets all the coolant drain out of the engine and cooling system components, and then top up with new coolant.
A coolant flush is more complex, and usually a bit more expensive. Instead of letting gravity do the work, flushing uses water pressure to blast any accumulated contaminants out of the cooling system’s passageways. Both the radiator and the engine block are cleaned out. The final step is to add new replacement coolant.
Should I get a coolant change or coolant flush?
While some shops may always recommend a coolant flush, they usually aren't necessary — a regular drain-and-fill will work fine. Always springing for a coolant flush will cost you more money than you need to spend.
Here are a few simple guidelines for whether you should drain or flush your coolant when it needs servicing:
Check your owner’s manual or warranty booklet to see what the manufacturer recommends. Most will simply say to change the coolant, which usually means a drain and fill. If you have a pretty new car, or you’ve been punctual with your routine maintenance schedule, your car should be just fine with this.
However, if the manufacturer recommends flushing your cooling system at certain intervals, then definitely do it. Make sure that any instructions that the manufacturer specifies for this procedure are followed.
If you have an older, possibly neglected vehicle with a cooling system problem, a coolant flush is the best choice. This is particularly the case if your coolant has become contaminated with corrosion, rust or debris.
Dirty or smelly coolant indicates that a system flush may be needed.