Once you know the engine (e.g., 4.2L I6, 5.3L V8), you can look up the correct Fram filter number using a cross-reference chart on the Fram website or an online auto parts store website (like AutoZone, Advance Auto Parts, or NAPA). Simply enter your vehicle's year, make, model, and engine.
Don't rely solely on generic answers. Using the wrong filter can damage your engine. Always check your owner's manual or use a parts lookup tool to ensure you get the correct filter for your specific Trailblazer.