Discover GMC Jimmy Catalytic Converter Prices & GMC Jimmy Exhaust Converters Price Replace GMC Jimmy Catalytic Converter Exhaust Leak. To ensure your GMC Jimmy's catalytic converter maintains peak performance, regular inspections are critical. Watch for signs of failure like decreased fuel efficiency or a persistent check engine light, signaling it may be time for a replacement. Extend its lifespan by using high-quality fuel and keeping your engine well-tuned. When choosing a new catalytic converter, consider direct-fit models for hassle-free installation or universal converters for a more cost-effective solution. Opt for converters made with durable materials to withstand the rigors of daily driving. By selecting the right type and maintaining it properly, you'll keep your Jimmy running smoothly and efficiently.