When to change serpentine belt on corolla 2004?

The serpentine belt on a 2004 Toyota Corolla should typically be inspected every 60,000 to 100,000 miles, or as recommended in the owner’s manual. Signs that it may need replacement include visible cracks, fraying, or a squeaking noise from the engine. If you notice any of these symptoms or if the belt has reached the mileage threshold, it's wise to replace it to avoid potential engine damage. Regular inspection during routine maintenance can help ensure optimal performance.