* Traditional green antifreeze (IAT): This is usually silicate-based and *generally* not compatible with newer antifreezes. Mixing it with other types, especially Dex-Cool (orange/red), can lead to problems like sludge formation, reduced cooling efficiency, and even damage to engine components. Your 2001 S10 likely used traditional green, but *you should check your owner's manual to be certain.*
* Modern "universal" green antifreezes: Some manufacturers now produce green antifreezes that are formulated to be compatible with other types, including Dex-Cool. These are usually labeled as "universal" or similar.
In short: While your 2001 S10 likely originally used traditional green, simply knowing the color isn't enough. Always check your owner's manual for the recommended coolant type. If you're unsure, it's best to flush the system and refill it with the correct antifreeze specified in your manual to avoid potential issues. Mixing different types of antifreeze is risky and could cause significant damage.
