Need a replacement catalytic converter for your 1979 Jeep J20? MagnaFlow offers high-quality catalytic converters engineered for 1979 Jeep J20 sub-models and engine sizes. We combine efficient design and state-of-the-art manufacturing to meet or exceed required emissions standards. Select your 1979 Jeep J20 requirements and state vehicle registration to buy the best J20 catalytic converter online that fits your '79 J20 and meets your state’s emissions compliance.