STP® Extended Life 50/50 Premix Antifreeze/Coolant

STP® Extended Life 50/50 Premix Antifreeze/Coolant is a long service life product based on a proprietary organic acid technology (OAT). This ethylene glycol based product is free of silicates, phosphates, borates, nitrates, nitrites and amines. It protects coolant system metals against rust and corrosion and provides excellent high temperature aluminum protection against temperature extremes, preventing freeze-up down to -37°C and boil over to 129°C (with a 100 kilopascal {15 psi} radiator cap in good condition). It is fully compatible with other similarly formulated OAT coolants and is recommended for use in newer model foreign and domestic cars and light duty trucks. When added as an initial fill, this coolant provides up to 250,000 km or 5 years service life protection in automotive applications.

For best results, STP® Extended Life 50/50 Premix Antifreeze/Coolant must not be mixed with conventional high pH, phosphate, borate or silicate containing coolants. This product has a distinctly orange colour to help differentiate it from conventional engine coolant, which is typically, but not always, green. While deleterious effects are not expected to be significant, the mixing of conventional coolants with STP® Extended Life 50/50 Premix Antifreeze/Coolant will result in a lower than expected lifetime (change-over intervals).

STP® Extended Life 50/50 Premix Antifreeze/Coolant offers the following advantages:

  • Extended service
  • Silicate, borate, phosphate, nitrite and amine free
  • Protects coolant system metals such as brass, copper, solder, steel, cast iron and aluminum
  • Compatible with other OEM and aftermarket similarly formulated organic acid technology (OAT) coolants
  • PREMIXED- No additional water required




STP® Extended Life 50/50 Premix Antifreeze/Coolant meets the performance requirements of the following specifications:

  • ASTM D3306
  • GM 6277
  • Japanese Standard JIS K2234
  • VW TL 774D
  • Ford WSS-M97B44-D

Product Packaging Specifications


Unit/Case Pack




3.78 L /4




Typical Product Properties

Characteristic Performance Test Method
pH 7.5 – 8.6 ASTM D1287
Specific gravityb 1.070 – 1.090 ASTM D1122
Freeze point, °C/°F -37/ -34 ASTM D1177
Foam volume, ml 150 max. ASTM D1881
Foam break time, second 5 max. ASTM D1881
Reserve Alkalinity, ml 2.0 min. ASTM D1121
Chloride, ppm 25 max. ASTM D3634
Colour Orange  
Glycol Content (wgt.%). 46 min.  
Inhibitors and Water Content (wgt.%) 54 max.  
Silicon (ppm) < 10 ASTM D6130
Boron (ppm) < 10  
Phosphorous (ppm) < 10  

b Measured at 15.6ºC/60ºF


Typical Coolant Performance Testing Results

Test Results¹ Max. Spec. Test Results¹ Max. Spec.
Copper 1 10 1 20
Solder 0 30 4 60
Brass 0 10 1 20
Steel -1 10 0 20
Cast Iron 2 10 0 20
Aluminum 0 30 2 60

1 Weight loss, except negative sign which indicate weight gain, per coupon in milligrams. Values are for coolant made from virgin ethylene glycol.

  Test Results¹ Specification
ASTM D4340 Heat Rejecting Aluminum Corrosion (mg/cm²/week) 0.3 1.0 maximum
ASTM D2809 Aluminum Water Pump Cavitation- Erosion Corrosion Rating 9 8 minimum

1 Weight loss per coupon in milligrams (average for 2 tests). Values are for coolant made from virgin ethylene glycol.

NOTICE: This product is shipped in compliance with applicable laws and regulations regarding classification, packaging, shipping and handling. The performance and physical property data described for this product are typical results not sale specifications, except where maximum or minimum is indicated. Refer to Material Safety Data Sheets for further information. Because use conditions and applicable laws may differ from one location to another and may change with time, the customer is responsible for determining whether product and the information in this document are appropriate for their use and for ensuring that their workplace and disposal practices are in compliance with applicable laws and other governmental enactments. Recochem’s warranty is limited to the claims of product meeting stated performance specifications. It is the responsibility of the end-user to determine product suitability as recommended in the owner’s manual and to follow engine manufacturer’s instructions.