Antifreeze Research and FAQs

[TomPierce]

It may be coming up on time to do some Preventative Maintenance, so I did some research on Coolants. To save you the time, I'll post the results in this thread. (See what happens where you have way too much time on your hands?)

Mods - I can't post in Maintenance where this really belongs - please move it for me? - thanks!

Coolant Shelf Life

The primary limiting factor in the shelf life of a coolant is silicate instability. Since silicate will eventually polymerize to silicate gel, all traditional coolants have a shelf life of about 18 months. DEX-COOL is silicate-free and therefore can be stored for at least 8 years without a problem provided the integrity of the container is maintained

Dilution

Optimum year round protection 50 percent (1 part anti-freeze/1 part water)
Maximum protection against freezing in extremely cold areas 67 percent (3 parts anti-freeze/2 parts water)
Greater than 67 percent or less than 50 percent are not recommended

Water

Deionized water or distilled water is preferred
Tap water is acceptable but not preferred
Do not use water softened with salts
Do not use well water as it normally is very high in mineral content.

Water is required to activate the chemicals in the corrosion and rust inhibitor package. Furthermore, adding water to antifreeze actually lowers the freeze-up and heightens the boil over protection provided. Pure antifreeze freezes at -13°. In comparison, a mix of 70% antifreeze and 30% water provides freeze-up protection down to -62°F and boil over protection up to 270°F.

Flushing and Filling

Using a chemical flush prior to the fresh fill of antifreeze/coolant is an effective way to remove deposits
Prestone® Super Flush for routine maintenance
Prestone® Super Radiator Cleaner to remove corrosion and lime scale

After flushing the end result will be an empty radiator and mostly water in the engine block and heater core. At this point, use a mix of 50% to 70% Coolant and water.

G8 Cooling System Capacity
3.6L V6 Engine 10.6 qt 10.0 L 2.64 gallons
6.0L V8 Engine 11.6 qt 11.0 L 2.90 gallon

Example: If the owners manual of your vehicle indicates that the capacity of the cooling system is 11.6 quarts, then you need to install 6 quarts of pure antifreeze. Note: Once the desired amount of concentrated antifreeze/coolant has been installed, the cooling system must be topped off with water to ensure a complete fill.

Prestone® products also offers a Flush N' Fill Kit for backflushing the cooling system. This backflush will remove more deposits than the chemical cleaner alone. Use one of the cleaners and then backflush the system.

Ethylene Glycol / Propylene Glycol

Ethylene glycol is used in antifreeze due to its properties as a freezing point depressant. When mixed with water 50% each the freeze point is -34°.

Propylene glycol is less toxic, which means that ingestion need not cause severe illness or death. When mixed 70% propylene glycol and 30% water the freeze point is -34°. You need a lot higher concentrate of propylene glycol than ethylene glycol to safely protect to -34°

Extended Life Coolant

A new type of antifreeze, referred to as extended or long life, has emerged. Its unique chemistry differs significantly from that used in traditional antifreezes. Referred to as organic acid technology (OAT), this new chemistry uses organic acids to protect cooling system metals. Extended life antifreezes have been colored red or orange depending on the supplier; however, more colors may be used in the future. While these fluids do not deplete during service, they also do not protect as quickly as IAT (inorganic acid technology) coolants. These differences require a significant change in procedures used to maintain the cooling system.

General Motors® has been using this technology (DEX-COOL®) in their cars and trucks since 1996. They use an orange dye for DEX-COOL® product. A Ford Motor Company® study concluded that OAT coolants "do not offer any significant advantages for the consumer" and "current coolant corrosion protection can be extended far beyond previous expectations".

Hybrid organic acid technology (HOAT) uses both inorganic and organic acid additives for long life protection. The objective with HOAT is to provide excellent all around protection and extended drain intervals. HOAT coolants
generally can replace or are compatible with green IAT in older vehicles. Chrysler used conventional green IAT coolant until 2001, when they adopted G-05®, a hybrid coolant. Ford followed suit in 2002, dropping the green IAT
for G-05® factory fill and extending the drain interval.

Added info:

- If you are going to a track (especially a road course), you should replace all coolant with water. Coolant is VERY slick and will cause a problem on the track.

- Coolant actually inhibits the cooling properties of water. If you are running a track day and wish to lower your engine temps by 10-15*, replacing the coolant mix with water will do that. Also, adding "Water Wetter" or "Purple Ice" will further lower the engine temps.

- If you live in an area of the country where it does not have hard freezes (occasional 30ºF nights don't count), then you can run water and Water Wetter/Purple Ice all year round. They have the necessary lubricants and chemicals added to make the water pump and other components work properly.

[Chewy]

Moved and added gallons to your post so that if people are getting pre-mixed like I like to then they know they will need 3 gallons.

Thanks for the post!
It's a sticky

Chris

[Napalm]

Great post man. I actually like the red/orange coolant. I've used it in the last 3 cars I've owned. I also like that you mentioned the back flush cleaning. Highly recommended, of insurance.

Oh and blades and gap sounds like a spark plug post.