Frequently Asked Questions



What is the shelf life of Prestone® Antifreeze/Coolant?

If the product is still in the original sealed container or has not been diluted with water then it has a shelf life of many years.

Does Prestone® Antifreeze/Coolant contain phosphates?

Some European automobile manufacturers request that a phosphate-free antifreeze be used in their vehicles. This issue is related to the extremely high mineral content of the water in Europe. If you were to mix an antifreeze that contained phosphates with the type of water they have in Europe, it may produce deposits that can settle in the cooling system and promote corrosion. However, in North America we do not have this type of water problem. Typical North American coolants have contained phosphates (which is part of the corrosion inhibitor package) for many years. Therefore, the question of phosphates is a non-issue here in North America. Prestone® Antifreeze/Coolant is completely safe for use in both foreign and domestic vehicles.

What is the best antifreeze/coolant concentration for a vehicle? Can I use 100% antifreeze?

We recommend that you use between a 50% and 70% concentration of antifreeze. At least 50% is necessary to give the adequate amount of corrosion protection, as well as freeze/boil-over protection. However, we do not recommend more than 70% antifreeze. This would cause restriction of the heat transfer capabilities, corrosion protection, and freeze protection. The concentration of freeze/boil-over protection of the antifreeze mixture can be checked using a Prestone® Antifreeze Coolant Tester.

Can I use extenders in place of SCAs and vice versa with Prestone® Heavy Duty Extended Life Antifreeze/Coolant?

Both SCA and Extender are used to supplement engine coolants to provide a fully formulated heavy-duty (HD) coolant. However, SCAs and Extenders are as different as conventional silicated HD coolant is to Extended Life HD coolants. SCA chemistry is typically based on a combination of nitrite and inorganic corrosion inhibitors, while Extenders are typically based on nitrite and organic corrosion inhibitors. The use of SCAs in Extended Life coolants or extenders in silicated formulations will negate the benefits of the additive and could jeopardize the cooling system’s life.

What automobile industry specifications do your antifreezes meet or exceed?

Prestone® Cor-Guard™ Antifreeze/Coolant is an Extended Life coolant that meets or exceeds the performance requirements of the following industry specifications:

  • ASTM D3306
  • ASTM D4985
  • SAE J1034
  • BS 6580 (European specification)
  • JACA/JSA-JIS K 2234-2006 (Japanese specification)
  • Australian AS2108-2004
  • Chinese GB 29743-2013
  • General Services Administration CID A-A-52624

In addition, Prestone® Cor-Guard™ Antifreeze/Coolant will meet or exceed the ASTM D 1384, D 4340, D 2570, D 2809, property characteristics and performance requirements of the following OEM/OE specifications:

  • Ford WSS M97B55-A
  • Ford ESE-M97B44-B
  • Ford WSS M97B44-D
  • GM 6722M
  • GMW 3420
  • Chrysler MS- 7170, MS-9769
  • Chrysler MS-12106
  • European and Asian Specifications

Prestone® LowTox® Antifreeze/Coolant is a propylene glycol based product that meets or exceeds the performance requirements of:

  • ASTM D3306
  • ASTM D4985
  • ASTM D6210
How do I flush my cooling system and install a fresh fill?

The video on this website (Prestone YouTube page) gives thorough directions for performing a flush and fill.  Following these easy to follow directions should revitalize your tired cooling system fluid and help your cooling system last longer.  

I have a leak in my cooling system; you offer several sealers. Which one should I use?

All of our sealers are high performing products. However, we offer them in various forms and in different strengths to give the consumer several options. We have found that many consumers are only comfortable using one specific form of sealer and that this form varies from consumer to consumer. Also, the size of the leak opening and the leak rate dictate which sealer to use. Of our high performing sealers, Prestone Radiator Sealer seals the largest leaks, while Prestone Radiator Stop Leak is more appropriate for handling the more frequently encountered small to medium leaks.

I'm constantly hearing about octane booster products. You say 0 to 60® can boost my octane by up to 10 points. What's a point and how does it relate to my car's performance?

The term "points" is commonly used in the automotive industry when referring to the octane increase a product offers. This is different from the figures shown at your local gas pump, where the octane "rating" of a gasoline is measured in "numbers." This can sometimes create confusion as to how "points" translate to "numbers."

The following calculation can be used to translate points to numbers:
1 octane point = 0.1 octane number.  Increasing the octane of gasoline has several positive effects on automobile performance. A higher octane gasoline will allow a car to run smoother by reducing knocks and pings, which ultimately restores lost performance.


Please Contact Us for any other questions.