How to Install AFE Direct Fit Catalytic Converter (97-99 4.0L Wrangler TJ) on your Jeep Wrangler

CAUTION: Allow time for your vehicle to cool down for atleast 2 hours prior to installation. When working on or under your vehicle proceed with caution. Exhaust systems reach high temperatures and may cause serious burns. Wear protective safety equipment; eye goggles and gloves to ensure a safe installation. aFe recommends professional installation on our products. 

Step 1: Support the vehicle on jack stands and disconnect the negative battery terminal from battery.

Step 2: Remove the O2 sensors between the FRONT & REAR of the OE cat.

Step 3: (NOTE: USE A FLOOR JACK TO SECURE THE TRANSMISSION). Remove the bolts on the cross member to the chassis as well as the (x4) nuts in the center of cross member (bolted to transmission) and remove the crossmember.

Step 4: Remove the (x1) bolt/nut for the clamp securing the catalytic converter to the stock exhaust system.

Step 5: Remove the (x2) bolts securing the catalytic converter to the stock exhaust manifold. Be careful when initiating this step. (Note: Removing the clamp could cause the catalytic converter to fall so it is a good idea to have a second hand when removing).

Step 6: Install aFe DFC (P/N: 47-48005). Before tightening bolts securing to OEM exhaust manifold and OEM exhaust system, make sure everything is positioned correctly.

Step 7: Re-install cross member to the transmission and chassis using the original nuts & bolts and tighten.

Step 8: Re-install O2 sensors (FRONT & REAR) to the aFe cat replacement.

Step 9: Re-check all your work.

Step 10: Remove vehicle off jack stands.

Step 11: Re-check all bolts/nuts after 50-100 miles of installation.