409S
®
Stainless Steel
This X-pipe assembly is designed to be used with either the factory mufflers or a Flowmaster axle-
back system. The steps on the following two pages are intended for customers replacing the center
resonator of their vehicle and retaining the use of the factory Mustang mufflers. If you are using the
new Flowmaster X-pipe along with a Flowmaster axle-back system, please see pages 3 thru 5 below.
10/10/16
Removal:
1)
Raise the vehicle up on a hoist or rack to working height. If you don’t have access to a hoist or
rack, raise the vehicle and support securely with jack stands. To ease the removal of the stock
system, spray a penetrating lubricant onto the bolts of the two clamp connections just forward of the
center resonator.
2)
Begin by measuring back 2 ½” from the beginning of
the straight area shown in the photo at left and make a
mark on both pipes. Support the exhaust system both in
front and behind the area to be cut. Check that the marks
are correct, then using a sawsall, cut both pipes at the
marks.
Note: Due to the closeness of the pipes to the
gas tank, use caution when cutting!
Carefully deburr the
end of the muffler inlet pipes where cut with a file or die
grinder.
Pg 1 of 6
Technical Support (707) 544-4761
Installation Instructions for:
X-PIPE #81107
2015-2017 MUSTANG
3.7L · V6 ENGINE
Fits Fast-Back and Convertible Models.
