What kind of antifreeze do you put in a 3100 engine?

A 3100 engine, referring to the Buick 3100 V6, should use a 50/50 mix of ethylene glycol-based antifreeze and distilled water. It's crucial to use an antifreeze that meets the manufacturer's specifications, often indicated as Dex-Cool or a similar coolant type. Checking your owner's manual is the best way to confirm the recommended type. Using the wrong type of antifreeze can damage the engine's components.