Product Tested

front label

Click above for larger image

back label

Click above for larger image

Prestone Products Corporation

Company and Product Information

Corporate Office:
1900 West Field Court
Lake Forest, IL 60045


Headquartered in Lake Forest, Ill., Prestone manufactures and markets antifreeze/coolant, brake and power steering fluid, and other leading vehicle maintenance products. Prestone Antifreeze/Coolant has protected vehicle cooling systems since 1927 and now features patented Cor-Guard™ Inhibitors.

Petroleum Quality Institute of America

Antifreeze/Coolant Test Program

The Petroleum Quality Institute of America (PQIA) is an independent resource for information and insights on the quality of lubricants in the marketplace. Our mission is to serve the consumer of lubricants by randomly sampling and independently testing lubricants taken from the field. Test results are posted along with the brand names on the PQIA website. This webpage provides an analysis on the brand detailed below.

The following are the test results for the sample examined.

Prestone 50/50 PREDILUTED
Extended Life Technology

Prestone 50/50 PREDILUTED
ANTIFREEZE/COOLANT Extended Life Technology

Manufactured by: Prestone Products Corporation in Lake Forest, IL

Purchased at: Edison, NJ

Date of purchase: 8/20/2015


Website(s): www.prestone.com

Test Results and Assessment:

The test results for this product are consistent with its labeled claims.

bottle icon Physical Properties pass
Chemical Analysis pass
Labeling warning

Note: Although laboratory tests alone cannot be used to establish if coolant meets standards, they can be used to determine if it doesn't.

Physical Properties and Chemical Analysis  Prestone
Percent Antifreeze, (Based on Percent Glycol) 50
Freeze Point, (ASTM D3321) in ⁰F -34
Bitterant, (ASTM D7704) in ppm 41
pH, (ASTM D1287) 8.16
Color, (Visual) Yellow
Chloride and Other Anions by Ion Chromatography (ASTM D5827)  
Glycolate, ppm Not Detected
Formate, ppm Not Detected
Chloride, ppm 4
Sulfate, ppm 7
Nitrite, ppm Not Detected
Nitrate, ppm Not Detected
Phosphate, ppm 1040