For example, OAT coolants should not be used in a vehicle that specifies the use of a hybrid OAT coolant.īut the short-lived nature of the corrosion inhibitors means this type of coolant should be changed every two to three years or 30,000 miles (though some products now claim a service interval of up to 50,000 miles with improved chemistry).

The fast-acting silicate and phosphate corrosion inhibitors provide quick protection for bare iron and aluminum surfaces, and have a proven track-record of providing trouble-free service in virtually any vehicle application (domestic, Asian or European), assuming the chemistry is correct. Traditional North American 'green' antifreeze, the original formula that everybody used until the introduction of today’s extended-life coolants. There are essentially three basic types of coolants: The more we get into the specifics of each type of coolant, the more confusing the whole discussion becomes – so we’re only going to tell you what’s really worth knowing with respect to the different types of antifreeze. What’s more, colors can change if somebody tops off the system with a different coolant. You can’t simply go by the color of the dye in the coolant because two coolants with similar colors may have different chemistry, and two coolants with different colors may have similar chemistry. For example, Ford and Chrysler specify hybrid OAT-only coolants. It’s important to always use the coolant chemistry recommended in the vehicle owner’s manual. These requirements are usually spelled out in the vehicle owner’s manual, and/or a decal or label on the coolant reservoir. We’re not going to summarize the whole laundry list of OEM coolants and colors here except to say each vehicle manufacturer has its own unique coolant specifications based on corrosion protection requirements, service life and chemical compatibility.

Audi coolant color