Purchase Toyota Sienna Exhaust Converters Replacement Cost & Toyota Sienna Catalytic Converter. Order Toyota Sienna Catalytic Converter Exhaust Pipe. Maintaining your Toyota Sienna's catalytic converter is crucial for ensuring peak performance and longevity. Regularly inspect for rust or damage and listen for rattling noises, which could signal it's time for a replacement. Enhance lifespan by using high-quality fuel and keeping the engine properly tuned. When selecting a new catalytic converter, consider options like direct-fit or universal converters; the former offers an exact match while the latter may require modifications but is often more cost-effective. Always opt for durable materials to withstand high temperatures and ensure professional installation for optimal function. By choosing wisely and caring for your converter, you'll ensure your Sienna remains a reliable companion on the road.