Rick's Free Auto Repair Advice

Radiator flush or cooling system service

Should I get a radiator flush or cooling system service?

Every Spring and Fall shops advertise specials on a radiator flush. You may think a radiator flush is the same thing as cooling system service. It’s not. A radiator flush is exactly what the term implies; the shop drains the radiator and refills it with coolant. But the radiator only holds a small portion of the coolant in your engine.

To do a complete cooling system service, you attach a cooling system flush machine

radiator flush, cooling system service

Typical cooling system flush machine

to capture all the old coolant (it must be recycled) as it pumps in fresh coolant. Cooling system service hookup and operation is more labor intensive and expensive than a radiator flush.

Most late model vehicles come from the factory with long life coolant. Many shops avoid stocking the exact coolant and instead rely on a “universal” coolant when doing a radiator flush or cooling system service. But car makers don’t recommend universal coolants because they may interact with plastics and rubber seals in the cooling system. In fact, many have issued service bulletins warning against using any non-recommended coolant.

Most older style engine coolants use a polyethylene glycol or polypropylene glycol base and silicate additives to prevent corrosion. The silicate coats internal metal parts to prevent galvanic action that can eat away at the radiator, heater core, water pump seals and bearings, and metal heater tubes. Read this post on the damage caused by the wrong coolant. However, the newer long life coolants are made with organic acid (OAT) or hybrid organic acid technology (HOAT). Both these chemistries have additives that must be compatible with the seals used in the engine. Switch to a different coolant and you can damage the seals.

So skip the radiator flush specials. They’re worthless. If your cooling system is due for service, take your vehicle to a shop that will flush with the factory recommended coolant.

©, 2015 Rick Muscoplat

Posted on by Rick Muscoplat

Custom Wordpress Website created by Wizzy Wig Web Design, Minneapolis MN