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Jeep Grand Cherokee 1993-1998: How to Replace Catalytic Converter

The catalytic converter in your Jeep Grand Cherokee is designed to neutralize harmful matter in the exhaust gasses that come out of your engine. A bad cat is bad for the environment, so do your share and replace that dead catalytic converter.

By Bassem Girgis - October 8, 2015

This article applies to the Jeep Grand Cherokee ZJ (1993-1998).

The Jeep Grand Cherokee's engine is constantly burning gas for the combustion process. However, not all the gases are burnt, and instead of letting it out in the world, the ingenious engineers of the OEMs created the catalytic converter. The catalytic converter (also called the "cat") is filled with exotic metals and compounds that have a chemical reaction with exhaust gasses, purifying your tailpipe emissions and ridding it of deadly NOx gas. If the catalytic converter goes bad in your Jeep, you will notice a rough ride, bad gas mileage, and most importantly, your car will fail the DMV's emission test, which means you won't be able to register your car. The government is pretty specific about emission and for good reasons, so replace your catalytic converter and save yourself the trouble.

Materials Needed

  • Wrench and sockets (set)
  • Jack and jack stands
  • New catalytic converter

Step 1 – Raise the car

Park your Jeep on a flat surface, raise your car from the front, secure it on jack stands, then raise it from the rear and secure it on two more jack stands.

  • Figure 1. Front jacking point.
  • Figure 2. Rear jacking point.

Step 2 – Remove the catalytic converter

Slide under the car, laying on your back. Locate the catalytic converter. You should see it in the middle of the car connected on the pipe. The front of it is pointing to the front of the car and is connected to the pipe that is coming from the engine, and the back of it is connected to the pipe going to the muffler.

Once you've located the exact location of the catalytic converter, unscrew the four bolts around it. There should be two in the front and two in the back in two U-bolts form.

  • Figure 3. Catalytic converter location.
  • Figure 4. There will be two U-bolts, making it four bolts total.

Pro Tip

Sometimes you will find that the catalytic converter is welded in instead of bolted. It's recommended that you take it to an auto shop, unless you know how to cut and weld, which is extremely dangerous given the tight space and the surrounding components.

Step 3 – Install the new catalytic converter

The new catalytic converter should fit in the same way as the old one was. Locate the arrow on it, and be sure it's pointing forward. Align it properly on the pipe, then install the two U-bolts with its four bolts.

Figure 5. Install the new catalytic converter.

Pro Tip

If you find out that you don't have U-bolts, the process is very similar. With the same idea in mind, separate the catalytic converter from the pipe by unbolting whatever bolts holding it together with the pipe.

Featured Video: Replacing Catalytic Converter

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