Talk to a Mustang Expert
Mon - Sun, 8:30 AM EST - 11:00 PM EST

Free Shipping On Orders Over $49. Details

How to Install a Flowmaster American Thunder Catback Dual Dump Exhaust - Stainless Steel on your 198

Installation Time

2 hours

American Muscle
Shop Parts in this Guide

Installation diagram for:

SYSTEM #817574


4.6L & 5.0L · V8 ENGINE


1) Raise the vehicle up on a hoist or rack to working height. If you do not have access to a hoist or rack, raise the vehicle and support securely with jack stands.

2) Separate the steel tailpipe hangers from the rubber mounts at the rear of each tailpipe. A lubricant may ease removal.

3) Using a hacksaw or sawsall, cut the stock tailpipes off approximately 2” behind the muffler case.

4) Remove the stock tailpipes from the vehicle and set aside.

5) Support the stock mufflers with a stand. Separate the steel muffler hangers on the rear of each muffler from the rubber mounts on the vehicle.

6) Remove the two nuts at the muffler to catalytic converter connection.

7) Remove the stock mufflers from the vehicle.


1) Position muffler #842548-183 on the right side of the car in the stock location. Install the nuts at the front of the flange connection. Connect the hanger rod on the muffler to the rubber mount on the vehicle. Level the muffler and tighten the front flange bolts securely. Repeat this step with left muffler #842548-182.

2) Slip one end of the turn down exit pipes into the muffler outlets and determine where you would like to position them. Install a provided 2ó" clamp and tighten enough to hold, but still allow for adjustment.

3) Adjust and align the position of the mufflers and turn downs to provide a satisfactory fit. Maintain at least 3/4” clearance around the new FLOWMASTER Exhaust System, the drivetrain and all chassis components.

6) After the hangers are adjusted to their final position, place the provided hanger keepers on the two muffler hangers. This will keep the hangers from slipping out of the rubber mounts.

7) For a cleaner appearance and more secure installation, we highly recommend welding all slipfit connections.

This guide applies to Vehicle years: 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998 and Submodels: Cobra, Foxbody, GT