Upgrading to a Mopar Challenger exhaust system is one of the most rewarding modifications you can make to your muscle car. Not only does it transform the sound into a deep, aggressive roar, but it also unlocks measurable horsepower gains and sharpens throttle response. Whether you are aiming for a menacing rumble at idle or a screaming wail at redline, a properly installed exhaust system is key. This guide covers every step in detail—from gathering tools and prepping your workspace to fine-tuning the final fit—so you can install your new exhaust with confidence and enjoy maximum sound and power.

Tools and Materials Needed

Before you begin, assemble everything you will need. Having the right tools on hand prevents frustrating trips to the hardware store mid-project and ensures a safe, clean installation.

  • Mopar Challenger exhaust system kit – Ensure the kit is the correct fit for your year and model (e.g., SRT, R/T, GT).
  • Socket set – A 3/8-inch drive set with standard and deep sockets (10mm, 13mm, 15mm, 18mm are common).
  • Wrench set – Combination wrenches in the same sizes as your sockets.
  • Jack and jack stands – A low-profile floor jack works best; always use stands for safety.
  • Safety glasses – Protect your eyes from rust, debris, and dripping fluids.
  • Mechanic’s gloves – Heat-resistant and cut-resistant gloves are ideal.
  • Exhaust hanger removal tool – A dedicated tool or a set of long-reach pliers.
  • Lubricant spray – Penetrating oil or silicone spray to loosen rubber hangers and bolts.
  • Torque wrench – To tighten critical fasteners to factory specifications.
  • Anti-seize compound – Apply to bolts and slip joints for future serviceability.
  • PB Blaster or similar penetrant – For rusted bolts and nuts (common on older vehicles).
  • Flashlight or work light – Under-car lighting is essential.
  • Shop rags or towels – For cleaning up grease and spills.
  • Optional: Exhaust pipe expander or spreader – Helps separate stubborn slip joints.

Pro Tip: Keep a factory service manual or online reference handy for torque specs and routing diagrams. Many Mopar kits include printed instructions, but reviewing them in advance saves time.

Preparing for Installation

A well-prepped workspace and car make the job smoother and safer. Follow these preparation steps before touching a single bolt.

Choose the Right Workspace

Work on a level, solid surface – preferably a garage floor or paved driveway. Avoid gravel or dirt, as jack stands can sink. Ensure the area is well-ventilated if the engine will be running during testing. Have a fire extinguisher nearby, especially if you will be working near fuel lines or the exhaust system while hot.

Safety First

Never rely solely on a jack. Always place jack stands under the vehicle’s designated lift points (the pinch welds located behind the front wheels and ahead of the rear wheels). Chock the rear wheels if only the front is lifted, or chock all four if the whole car is raised. Wear safety glasses and gloves throughout the process. The exhaust system can be sharp, and old systems often have rusted edges.

Let the Car Cool

If the engine has been run recently, let the exhaust system cool completely. Exhaust components can exceed 400°F (200°C) and cause severe burns. A cold system also makes it easier to handle and avoids heat-softening rubber hangers prematurely.

Remove Any Obstructions

Check for factory heat shields, spare tire crossmembers, or aftermarket parts that might interfere. On some Challenger trims, you may need to temporarily remove the spare tire or a brace for better access to hangers. Inspect the catalytic converter flanges and the bolts connecting the mid-pipe – they are often the most stubborn.

Step-by-Step Installation Guide

Follow these steps carefully. Work methodically, and do not force anything that seems stuck – use penetrant and patience.

Step 1: Lift the Vehicle Securely

Position the jack under the front crossmember or factory-recommended lift point. Raise the front of the car until the wheels are off the ground, then place jack stands under the front pinch welds. Lower the jack gently so the stands bear the weight. Repeat for the rear if you need all four wheels off the ground (recommended for full exhaust replacement).

Note: If you are only replacing the cat-back portion (from the catalytic converter back), lifting the rear alone may suffice. However, lifting the entire car gives you easier access to all hangers and bolts.

Step 2: Remove the Old Exhaust System

This is often the most labor-intensive part, especially if fasteners are rusty.

2a. Lubricate All Fasteners and Hangers

Spray penetrating oil (like PB Blaster) onto every bolt, nut, and rubber hanger you will touch. Allow it to soak for at least 10 minutes. While waiting, you can loosen the clamps on the muffler and mid-pipe connections.

2b. Detach the Rear Section

Start at the rear of the car. Use the exhaust hanger removal tool to pull the rubber hangers off the metal studs on the muffler and tailpipes. Work from one side to the other, supporting the exhaust as you go. It helps to have a helper hold the muffler while you release the hangers. Once all hangers are free, lower the rear section and set it aside.

2c. Remove the Mid-Pipe and Front Section

Move forward to the catalytic converter flanges. Use a socket and wrench to unbolt the mid-pipe from the catalytic converter. If the bolts are rusted, apply more penetrant and use a breaker bar. You may need to use a 6-point socket to avoid rounding. Once unbolted, remove the hangers supporting the mid-pipe and lower it out from under the car. Some Challengers have an H-pipe or X-pipe in this area – remove it in one piece if possible, or cut it if it’s badly rusted (but be careful not to damage surrounding components).

Tip: If the slip joints between the mid-pipe and muffler are seized, use an exhaust pipe spreader or a pry bar carefully to separate them. Heat from a propane torch can also expand rusted joints, but use caution near fuel lines and brake lines.

Step 3: Prepare the New Mopar Exhaust System

Unbox the kit on a clean, flat surface. Lay out all components in the order they will be installed: front pipes (if included), mid-pipe or X/H-pipe, mufflers (or resonators), tailpipes, and tip assemblies. Check that all included hardware (bolts, gaskets, clamps) matches the instructions. If your kit includes a gasket flange, inspect it for flatness.

3a. Apply Anti-Seize to Slip Joints

Apply a thin layer of anti-seize compound to the inside of each slip joint. This prevents corrosion and makes future removal much easier. Do the same for the threads of all bolts and nuts.

3b. Test-Fit the Assemblies

Before final tightening, loosely assemble the entire system on the ground to ensure alignment. Mopar kits are generally precise, but manufacturing tolerances can vary. Check that the pipes fit together without binding and that the hanger tabs are oriented correctly.

Step 4: Install the New Exhaust System

Begin at the front of the car and work backward. This ensures proper alignment with the catalytic converter and engine.

4a. Attach the Front Section to the Catalytic Converter

Bolt the front pipe (if separate) or the mid-pipe directly to the catalytic converter flange. Use a new gasket if provided (most Mopar kits include a high-performance gasket). Hand-tighten the nuts, then torque to specifications (typically 25–35 ft-lb, but refer to kit instructions).

4b. Connect the Mid-Pipe and X/H-Pipe

Attach the remaining sections using the provided band clamps or slip joints. Do not fully tighten yet – leave clamps snug but loose enough to allow adjustment. This is crucial for achieving proper clearance around the driveshaft, heat shields, and rear differential.

4c. Install the Mufflers and Resonators

Position the mufflers or resonators (depending on your kit) and connect them to the mid-pipe. Attach the tailpipes. Insert the rubber hangers into the mounting points on the underbody and then onto the metal tabs on the exhaust. Use a lubricant spray on the rubber to make insertion easier. Check that each hanger is fully seated.

4d. Align and Tighten All Clamps

With everything loosely connected, walk around the car and adjust the exhaust as needed. The tips should sit evenly in the bumper cutouts, and the pipes should have at least 1/2 inch clearance from any suspension components, driveshaft, brake lines, and the fuel tank. Once satisfied, tighten all band clamps and bolts from front to rear. Use a torque wrench for critical points (check your kit instructions).

Important: Over-tightening band clamps can deform the pipe or strip the clamp. Torque to the specified value, typically 30–45 ft-lb for most Mopar exhaust clamps.

Step 5: Secure the Exhaust System and Final Checks

After tightening, give each hanger a gentle tug to ensure it’s locked. Verify that the exhaust does not contact any body panels or the floorpan – especially under the rear axle area. Crank the steering from lock to lock while watching the exhaust clearance if your car has an active exhaust valve or moving parts nearby.

If any parts are too close, loosen the relevant clamps and adjust. Re-tighten after adjustment. This step is critical to prevent rattles, droning, or heat damage to nearby components.

Post-Installation Checks and Tuning

Now that the hardware is in place, it is time to bring the system to life and ensure everything functions correctly.

Start the Engine

Without starting yet, check all connections one more time. Then start the engine and let it idle. Listen for exhaust leaks at every joint – a hissing or ticking sound indicates a gasket leak or improperly sealed slip joint. If you hear a leak, tighten the closest clamp or replace the gasket. A small leak can worsen over time and may affect performance and sound quality.

Inspect for Smoke or Odors

With the engine running, look under the car for smoke (from anti-seize burning off, which is normal) or smell for burning materials. If the exhaust is too close to a heat shield or wiring, you may smell melting plastic. Address immediately by adjusting the pipe location.

Test Drive

Take the car for a short, moderate-speed drive. Vary engine RPM and listen for drone frequencies, rattles, or contact. Bring it back and inspect the system again while it is still warm but not hot. Look for any signs of movement, discoloration from contact, or loosened clamps. Re-torque if needed.

Let the System Break In

New exhaust systems often change sound slightly as they accumulate miles and heat cycles. The packing in the mufflers settles, and the metal takes a set. Give it two to three hundred miles before judging the final tone or performance gains. During this break-in period, avoid prolonged full-throttle runs.

Benefits of Upgrading Your Exhaust System

Investing in a Mopar Challenger exhaust system delivers multiple advantages that go beyond just noise.

  • Improved Sound: Expect a deeper, more aggressive exhaust note with minimal drone. Mopar systems are engineered to enhance the natural character of the Hemi V8 (or V6 for GT models) without being obnoxious.
  • Enhanced Performance: Reduced backpressure improves volumetric efficiency, leading to better throttle response and typically gains of 5–15 horsepower and similar torque increases, depending on your specific kit and vehicle.
  • Increased Fuel Efficiency: A more efficient exhaust can yield a modest improvement in highway fuel economy – often 1–2 MPG – when driving conservatively.
  • Durability: Mopar parts are designed to meet or exceed OEM standards. Stainless steel construction resists corrosion and outlasts stock aluminized systems.
  • Better Aesthetics: Mopar exhaust tips are usually larger and more polished, giving the rear of the Challenger a more aggressive, finished look.

For more information on specific gains, check out Mopar's official exhaust page or Challenger Talk forums for real-world dyno results. You can also read this Hot Rod article on Mopar exhaust install tips for additional insights.

Conclusion

Installing a Mopar Challenger exhaust system is a weekend project that transforms your driving experience. By following this detailed guide – from proper preparation and careful removal of the old system to precise alignment and post-installation checks – you ensure optimal sound, performance, and longevity. The sense of accomplishment you feel when you first hear that throaty idle and then feel the power on the road is unmatched. Enjoy your ride, and let that Hemi sing.