ASTM D7715 Standard Specification for Fully-Formulated Glycerin Base Engine Coolant for Heavy-Duty Engines
4. General Requirements
4.1 Concentrated and prediluted coolants shall meet all of the physical, chemical and performance requirements of Specification D7714, Tables 1, 2, and 3.

4.2 The coolant concentrate mixed with water or the prediluted coolant, when maintained with maintenance doses of SCA in accordance with the engine manufacturer's recommendations, and those on the product label, shall be suitable for use in a properly maintained cooling system in normal service for a minimum of two years (see Appendix X1).

5. Additional Requirements
5.1 The coolant concentrate or prediluted coolant additionally shall provide protection in operating engines against cavitation corrosion (also termed liner pitting) and against scaling of internal engine hot surfaces. Hot surfaces typically are within the engine head, head spacer, upper cylinder liner, or liquid cooled exhaust manifold (Test Method D7583).

5.2 Lack of compatibility between the coolant and SCA product's chemistry may cause the solute to precipitate out of solution, with potential adverse effects in the vehicle or engine cooling system. A test procedure for compatibility (Test Method D5828) has been developed and approved. The compatibility of SCA and coolant concentrate solutions meeting this specification shall be determined using (Test Method D5828) and the results reported.

5.3 Both the concentrated and prediluted coolants shall contain less than 50 µg/g sulfate ion.

6. Keywords
6.1 cavitation; fully-formulated heavy-duty engine coolant; glycerin; supplemental coolant additive maintenance dose