Install Guide: 2015-2017 Mustang GT Cat-Back Exhaust

Install Guide: 2015-2017 Mustang GT Cat-Back Exhaust

Last Updated July 21, 2021 | Bill Tumas

S550 Mustang GT Cat-Back Exhaust Installation

Mustang owners have always appreciated the throaty growl of a good exhaust, which frequently means modifying the factory system. The S550 Mustang is no different. The exhaust isn't bad from the factory, but it has a very mellow sound and would definitely benefit from something a little more aggressive. And that is where the Sport Cat-Back Exhaust from Ford Performance and Borla steps in to offer a much deeper and throatier exhaust note.

CJ Installation Video

Step-By-Step Instructions:

Tools Required:

  • Lift or Jack and Jack Stands
  • 3/8” Ratchet
  • 13mm Deep Socket
  • 15mm Deep Socket
  • 6” Extension
  • Safety Glasses

Installation Time: ~1 hour

Difficulty: Moderate

2015 Mustang GT Cat-Back Exhaust Install Tools

  1. You’re going to start by removing the two clamps that bolt the factory cat-back to the factory H-pipe. Once loose, you can pull the tabs out a bit and slide the clamps back. 2015 Mustang GT Cat-Back Exhaust Install Slide Clamps Back
  2. Once the front clamps are loose and moved back towards the tailpipes, you can loosen and remove the bolts connecting each hanger to the rear subframe. 2015 Mustang GT Cat-Back Exhaust Install Loosen Clamps
  3. There are two additional hangers on each muffler located on towards the front on either side. At this point, you’ll need to actually slide the exhaust off the connection at the mid-pipe where you slid the clamp back in Step #1. Then, then slide the entire system towards the front of the car in order to get it off the muffler hangers. Once the mufflers drop, you can remove the entire system from the car.

    Tech Tip(s): You’re going to want extra help for this part, the factory exhaust is all one piece and it's quite heavy. If it’s difficult to slide out of the hanger, spray some WD-40 or another lubricant to aid the removal process. Also, be sure to put a couple microfiber cloths around the tips so you don’t damage your valence upon removal. 2015 Mustang GT Cat-Back Exhaust Install Protect Bumper Cloth 2015 Mustang GT Cat-Back Exhaust Install Remove Factory System
  4. Remove the (2) clamps and (2) black subframe hangers off your factory exhaust. Take the black subframe hangers and slide those on your new Ford Racing by Borla intermediate pipes. Make sure the hook on the hanger goes towards the body of the car. Then, slide the remaining (2) clamps on your Ford Racing by Borla X-Pipe and install on the car with the studs facing down so you can easily access the nuts. Make them snug, but don’t completely tighten them just yet. 2015 Mustang GT Cat-Back Exhaust Install OE Clamps New Pipe
  5. With the (2) black subframe hangers in place and installed on your new Ford Racing by Borla intermediate pipes, you can now slide them into place. Grab an included clamp and install each intermediate pipe into place. Make the clamps snug, but do not completely tighten them just yet. 2015 Mustang GT Cat-Back Exhaust Install New Pipe 2015 Mustang GT Cat-Back Exhaust Install Tighten Clamps
  6. After putting a clamp on either Ford Racing Muffler pipe, you’re ready to install them on the vehicle. You want to slide the muffler through the hanger all the way in the rear and twist it into place. 2015 Mustang GT Cat-Back Exhaust Install Slide Muffler Through 2015 Mustang GT Cat-Back Exhaust Install Twist Into Place
  7. Once you have the muffler where you want it, snug the clamp. 2015 Mustang GT Cat-Back Exhaust Install Snug Clamps
  8. Repeat the process on the other side and fully tighten down all of your clamps. Start at the front and work your way back. Take note when tightening where the tips are inside the rear valence and adjust as necessary. 2015 Mustang GT Cat-Back Exhaust Install Final Product

Some Notes On The Exhaust Note/Drone

Now of course, you’re all probably wondering what kind of sound this exhaust produces. This system is a huge improvement over the stock exhaust setup. It offers a real aggressive sound, which is exactly what we were looking for out of our S550 GT.

From outside the car, it has a nice, muscle car tone to it but it's not overly loud in volume. It definitely doesn’t sound stock inside or out, but not bad at all for normal driving.

Inside the cabin, you can expect to notice that you have it installed in comparison to the stock system, but drone is minimal and barely noticeable at highway speeds until you get into the accelerator pedal.

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Please Note: Please keep in mind that this guide is a tool to help you install the parts on your vehicle. If you don’t feel confident in performing this installation properly on your own, have a professional install the parts for you.

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About the Author

Bill is our resident Mustang expert with over 25 years in the auto industry. He’s produced hundreds of videos as the host of the CJ Pony Parts YouTube channel. Read full bio →

Install Guide: 2015-2017 Mustang GT Cat-Back Exhaust

Ford Racing and Borla teamed together to produce this Stainless Steel Cat-Back Bolt-On Exhaust System that fits your 2015-2017 Mustang. It starts with a True X-Pipe, mandrel-bent tailpipes, a pair of Borla mufflers, and a set of polished 4-1/2” Ford Racing tips. This is a direct bolt-on for your 2015 Mustang and requires no cutting for installation.

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