This specification covers the general, physical, chemical, and performance requirements for supplemental coolant additives for use as precharging coolants in the cooling systems of heavy-duty engines. Test solutions shall be standard corrosive water, ethylene or propylene glycol in standard corrosive water, and NaCl dissolved in a solution of glycol in deionized water. These test solutions shall comply to the specific limits for the following requirements: corrosion in glassware mass loss; simulated service test mass loss; foaming; water pump cavitation erosion-corrosion rating; corrosion of cast aluminum alloys at heat-rejecting surfaces; ultrasonic cavitation resistance; supplemental coolant additive-glycol base coolant compatibility; hot surface scaling and deposits resistance; effect on nonmetals; storage stability; ash, chloride ion, and silicon contents; pH in distilled water; reserve alkalinity; and the effect on vehicle finish.

1.1 This specification covers the general, physical, chemical, and performance requirements for Supplemental Coolant Additives (SCAs) at a precharged level in the cooling systems of heavy-duty engines.

Note 1—After precharging, SCAs are customarily used periodically to service cooling systems at ¼ to ¹/₃ the precharged dosage to compensate for additives lost through dilution and depletion.

1.2 The SCA products meeting this specification are intended for use with water, with recommended dilutions of coolant concentrates, with prediluted engine coolants, or to upgrade the performance of light-duty engine coolants to meet the heav-duty requirements of Specification D6210. Engine coolant products shall be of the low-silicate type and, if ethylene glycol based, shall meet Specification D4985. Propylene glycol base low-silicate type coolant products may also be used, if these materials meet the chemical and performance requirements of Specification D4985.

1.3 The SCA concentrate, before dissolution, may be in either liquid, solid, or slurry form. The form is as agreed upon between the manufacturer and the user.

1.4 The values stated in SI units are to be regarded as standard. The inch-pound units in parentheses are approximate equivalents provided for information only.

1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.