How to Install a Stainless Works 3 in Retro Chambered Catback Exhaust in Your 2015-2016 Mustang GT

Thanks for purchasing a Stainless Works Catback for your 2015 Mustang GT 5.0. We have gone to great pains to make sure that our exhaust systems fit and sound great. Please follow these steps to ensure that your installation goes as planned.

 
1.  Stainless Works recommends the use of Permatex Hi-Temp RTV silicon gasket 
maker as an option to or in conjunction with the use of factory gaskets. The 
recommended RTV is Sensor-Safe P/N 101BR or 27BR, available at NAPA and 
other retailers.

2.  Disconnect the battery before starting work on the exhaust system for your 
vehicle. Reconnect the battery when the job is completed.

3.  Your exhaust system can be installed by a weekend warrior but the use of a lift is 
recommended for ease of installation. If using a jack, the vehicle must be placed 
on a level hard surface and jack stands are required for safety reasons.

4.  Raise and support vehicle.

DISASSEMBLY

5.  Loosen clamps at factory connection point behind the transmission and save if 
installing the catback to factory manifolds.

6.  Unbolt (2) 8mm bolts from tailpipe rubber hangers and remove these from rear 
sub frame (save the bolts and hangers).

7.  Remove exhaust from rear hangers and car. This may take two people.

ASSEMBLY

8.  Install H-pipe or X-pipe depending on which product you have purchased using 
two factory clamps removed previously in step #5. The Catback to the factory 
manifolds is sized at 2-1/4” OD at the front for connecting to factory manifolds. 
If you purchased the Performance Connect Catback to go with Stainless Works 
Headers, you will have an X-pipe or H-pipe which is sized at 3” ID at the front. 
Installation of this will require two 3” clamps, supplied with the Catback.

9.  Install 24” long chambered mufflers to H or X-pipe using (2) 3” clamps.

10. Install right and left tails using (2) 3” clamps.

11. Install rear chambered mufflers with integrated tips to hangers and tail pipes using 
(2) 3” clamps.

12. Reinstall rubber hangers removed from step #6 above, using (2) 8mm bolts.

13. Level the H-pipe or X-pipe and chambered mufflers and snug clamps.

14. Adjust and tighten the system from front to back.

15. Be sure to have adequate clearance around all wires, hoses and lines. If anything
is in contact with the exhaust system, it will melt. Make sure to have at least ½” of clearance and wrap any suspect areas with DEI thermal barrier wrap.

16. Lower vehicle.

17. After double checking for clearance and making sure all lines, wires and hoses are 
secured, drive the car for 10-20 miles and re-check all clamps and clearances.
Your system may be tack welded at the joints/ clamps to reduce shifting of the 
system during heating and cooling cycles. Make certain to disconnect the battery 
before performing any welding.