In the manual of my vehicle, CAT recommends using their SCA over others. Is this just marketing or do different brands create different SCAs that affect longevity/chemical interaction/etc?
What is the chemical difference between various brands of coolant additives (SCAs) for the cooling system?
@Moab That's interesting. My manual specifically says DCA in connection with the coolant and says this multiple times. LOL if they made a mistake. Regardless, I've updated my question to say SCA instead. thanks– Joe BOct 11, 2019 at 3:36
You are correct they are one in the same. Although I cannot find DCA anywhere on the CAT site I do find SCA here....parts.cat.com/en/catcorp/217-0617– MoabOct 11, 2019 at 12:41
Only reference I find for DCA is in this fleetguard PDF......cumminsfiltration.com/russia/sites/…– MoabOct 11, 2019 at 12:44
1@Moab It's in my manual for the CAT3126 by Thomas (vehicle is a school bus). It's from '91 so I assume they've changed their language around it.– Joe BOct 11, 2019 at 17:32
It's not just marketing - although there is a lot of money to be made from vehicle care and parts.
The coolant additive must protect the engine from corrosion, cavitation, and scale. Different engine types run at different temperatures, and there are various coolant standards for them. Also, some engines are made of aluminium, others of iron, and they need different coolant additives.
Cummins Filtration in their guide "What You Don’t Know Can Hurt Your Engine: An Introduction to Coolant Technology & Best Practices" (8th in the right column) says
Determining which coolant product is right for your application can be a difficult decision. Many customers mistakenly choose based on the color of the coolant, however, manufacturers do not use standard color conventions and coolants of the same color are not guaranteed to be similar in composition. A working knowledge of how coolants are classified can be helpful in determining the difference between coolant products and understanding which product is appropriate for each application and situation.
The vehicle is originally under warranty and the simplest way of ensuring you use the right coolant additive is to specifiy which one to use (or invalidate the warranty).