Need a replacement catalytic converter for your 2004 Ford Thunderbird? MagnaFlow offers high-quality catalytic converters engineered for 2004 Ford Thunderbird sub-models and engine sizes. We combine efficient design and state-of-the-art manufacturing to meet or exceed required emissions standards. Select your 2004 Ford Thunderbird requirements and state vehicle registration to buy the best Thunderbird catalytic converter online that fits your '04 Thunderbird and meets your state’s emissions compliance.