Specifications to Consider
Engine coolants for heavy-duty use must meet ASTM D6210 for heavy-duty use. A true D6210 test includes the John Deere Cavitation Test (ASTM D7583) that ensures that the nitrite-free engine coolant does not cause pitting and cavitation in wet-sleeve or replaceable piston liners.
MAXTECH® HD Engine Coolants meet D6210 performance test and is safe for use in all heavy-duty diesel engines.
Why is it Red?
The American Trucking Association’s Technology and Maintenance Council (TMC) in it’s recommended practices (RP365) has proposed guidelines for the color of engine coolants based on formulation in attempts to standardize and prevent confusion. Conventional, EG-based, low silicate coolants are recommended to be green; fully formulated, EG-based coolants are recommended to be pink/purple; and organic acid technologies (OAT) are recommended to be red.
What the OEM's are Stating
Detroit Diesel DDC-SVC-BRO-0002 2015: “Detroit has found that ELC’s containing nitrite may lead to a breakdown of the coolant and subsequent damage to the cooling system. Nitrite Organic Acid Technology (NOAT) must not be used in Detroit engines because with poor maintenance components become more vulnerable."
Cummins: SU1403 - “Some OAT coolants do not need nitrite and/or molybdates for liner pitting.” Cummins manufacturers their own NF OAT.
Cummins LT36442; March 31, 2015: Conventional coolants will have the highest total cost of ownership and can cost up to ten times more than premium ELC coolants over the life of a vehicle.” “The preferred method of manufacturing aluminum radiators uses a process that can introduce contamination into a system and cause corrosion. OAT coolants are typically more robust for protecting against this type of contamination than are nitrited OAT (NOAT), hybrid, or conventional coolants"
Navistar: “Because nitrites cause corrosion to aluminum cooling systems, 2010 emissions compliant Maxxforce 11 & 13 engines come equipped with nitrite-free coolant standard."
The Technology & Maintenance Council (TMC) of the American Trucking Association (ATA) has set helpful guidelines for engine coolant color determinant upon the coolant chemistry formulation. TMC RP 365 breaks it down quite simply into the following delineations:
RP 302C: Conventional Low Silicate is recommended to be green
RP 329A: Fully Formulated Ethylene Glycol is recommended to be purple/pink
RP 330: Fully Formulated Propylene Glycol is recommended to be blue
RP 364: Organic Acid Technology (OAT) is recommended to be red
Unfortunately, in the light duty / passenger vehicle world, color doesn't really mean anything at all. The color variations are mainly to influence the after-market purchase to benefit the OEM - the OEM wants the consumer to purchase their brand of coolant. For example, Genuine Toyota Super Long Life is pink and while there are many chemically equivalent coolants in various color options, it's a lot easier for the consumer to pick a pink coolant and hope they've selected correctly. However, complicating matters more, there are blue coolants which are chemically equivalent to pink and while many gold/yellow coolants make the claim to be "global" or "universal", that may in fact not be suitable for your vehicle. Confused yet? It's more important to understand the chemistry of the coolant or the type versus the color since color is just a dye.
There is some good news at least in the heavy duty world. The Technology Maintenance Council (TMC) of the American Trucking Association (ATA) has set some standards for the color of a coolant based on it's chemical formulation. Perhaps the automotive industry should adopt some guidelines to better serve their customer? Learn more about those TMC classifications by viewing the article TMC Guidelines for HD Coolant Color.
Learn more about engine coolants here.