818147 Force II Exhaust Kit
Product Information: – Product Name: Flowmaster Force II Exhaust
Kit – Compatible Vehicle: 2015-20 Ford F-150 with 2.7L, 3.5L, and
5.0L Engine – Compatibility: 2- or 4-Wheel Drive; 145-Inch
Wheelbase Only – Manufacturer: Flowmaster – Website:
www.flowmastermufflers.com – Technical Support: (866) 464-6553
Product Usage Instructions: 1. Review the instructions and verify
the kit contents: – Use the parts drawing and list provided to
verify the contents of your Flowmaster Force II exhaust kit. – If
any parts are missing, contact Flowmaster Technical Support for
replacements. 2. Raise the vehicle to working height on a lift or
securely support it on jack stands: – If using a lift, the entire
stock exhaust system can be removed as a whole by two persons. – If
performing the installation on jack stands, cutting the tailpipe
off makes removal easier. 3. Remove the factory exhaust system: –
Cut the tailpipe off just behind the muffler. – Disengage the
tailpipe’s hanger rod from its rubber isolator and remove the
tailpipe from the vehicle. – Remove and discard the 2 fasteners
from the inlet pipe flange. – Slide the exhaust system back,
disengage the 2 or 3 hanger rods on the muffler from their
isolators, and remove the inlet pipe and muffler from the vehicle.
4. Install your Flowmaster exhaust system: – Before installing any
clamps, remove their nuts, apply antiseize compound to the bolt
threads, and re-install the nuts. – Note: All pipe-to-pipe slip-fit
connections must seat 3 inches deep. All pipe-to-muffler
connections must seat 2 inches deep. Mark the male ends of each
pipe in advance to ensure proper insertion during assembly. – On
the driver’s side frame, between the leaf spring and the spare
tire, install the frame hanger (14) with its rod pointing inboard.
Use the 3-1/2 bolt (15) against the hanger on the outside of the
frame, and use the backing plate (16), lock washer (12), and nut
(11) on the inside of the frame. Lastly, slide the rubber hanger
(17) onto the rod. – Slip the 3-inch clamp (8) onto the head pipe.
Slip the muffler (2) onto the head pipe, support it with a stand,
verify 2 inches of insertion, and snug the clamp slightly to allow
for final adjustment later. – Continue following the installation
instructions provided in the user manual to complete the
installation of your Flowmaster Force II exhaust kit. For
additional assistance or specific applications, refer to the
Applications tab on the product web page or contact Flowmaster
Technical Support at (866) 464-6553.
ITEM PART NO.
DESCRIPTION
QTY.
1 26625S
HEAD PIPE
1
2 8530552-Z
FORCE II MUFFLER
1
3 86323S
LEFT OVER-AXLE PIPE
1
4 86327S
RIGHT OVER-AXLE PIPE
1
5 86324S
LEFT TAILPIPE
1
6 26629S
REAR EXIT PIPE
2
7 ST462
TIP, STAINLESS STEEL
2
8 MC300BS
CLAMP, STAINLESS, 3″
1
9 MC250BS CLAMP, STAINLESS, 2-1/2″ 5
10 HW211
BOLT, 3/8-16 × 2″
2
11 HW103
NUT, 3/8-16
3
12 HW309
LOCK WASHER, 3/8″
3
13 HW303
FLAT WASHER, 3/8″
4
14 226HA
FRAME HANGER
1
15 HW234
BOLT, 3/8-16 × 3-1/2″
1
16 HA226
BACKING PLATE
1
17 HA168
HANGER, RUBBER
1
18 HW502
HANGER KEEPER, 7/16″
2
19 HW505
CABLE TIE, 15″
1
16 12 11 17
Installation Instructions
818147
2015-20 FORD F-150 with 2.7L, 3.5L, and 5.0L ENGINE
2- or 4-WHEEL DRIVE; 145-INCH. WHEELBASE ONLY
See “Applications” tab on the product web page for specific applications.
10 (×2) 13 (×2)
13 (×2) 12 (×2) 11 (×2)
1
8
2
9 (×2)
3 4
9 5
818147 Rev 01/03/23
9 15 14 18
6
19 7
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NOTES
· Installation requires moderate mechanical skill. If this job is beyond your abilities, seek the services of a qualified technician.
· If you do not understand any part of these instructions, please call Flowmaster Technical Support at (866) 464-6553 for assistance.
· Use stands to support exhaust system components, both when removing the stock system, and when installing your new kit.
· Apply penetrating oil generously to clamps, fasteners, pipes, and hanger rods for ease of disassembly.
REVIEW THE INSTRUCTIONS & VERIFY THE KIT CONTENTS
Take a moment to read and understand these instructions before installing your Flowmaster Force II exhaust kit.
1. Raise the vehicle to working height on a lift. If you do not have a lift, securely support the vehicle on jack stands.
NOTE: If a lift is used, the entire stock exhaust system can be removed, whole, by two persons. But cutting the tailpipe off makes removal easier, especially if the job is performed on jack stands.
CUT
Use the parts drawing and list to verify your kit’s contents. In the unlikely event that any parts are missing, please contact Flowmaster Technical Support for replacements.
HANGER
2. Cut the tailpipe off just behind the muffler. Disengage the tailpipe’s hanger rod from its rubber isolator, and remove the tailpipe from the vehicle.
REMOVE THE FACTORY EXHAUST SYSTEM
WARNINGS
· AVOID BURNS! Exhaust systems get extremely hot. Allow the vehicle to cool down fully before starting work.
· AVOID SERIOUS INJURY OR DEATH BY CRUSHING! Never work under a vehicle that is supported by jacks.
3. Remove and discard the 2 fasteners from the inlet pipe flange
818147 Rev 01/03/23
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1 OR 2 RODS AT FRONT
1 ROD AT REAR
4. Slide exhaust system back, disengage the 2 or 3 hanger rods on the muffler from their isolators, and remove the inlet pipe and muffler from the vehicle.
INSTALL YOUR FLOWMASTER EXHAUST SYSTEM
16 12 11
15 14
7. Before installing any clamps, remove their nuts, apply antiseize compound to the bolt threads, and re-install the nuts.
NOTE: All pipe-to-pipe slip-fit connections must seat 3″ deep. All pipe-to-muffler connections must seat 2″ deep. Mark the male ends of each pipe in advance, to ensure proper insertion during assembly.
17
5. On the driver’s side frame, between the leaf spring and the spare tire, install frame hanger (14) (with its rod pointing inboard) using the 3-1/2″ bolt (15) (against the hanger, on the outside of the frame), and backing plate (16), lock washer (12), and nut (11) (on the inside of the frame). Lastly, slide rubber hanger (17) onto the rod.
8 2
8. Slip the 3″ clamp (8) onto the head pipe. Slip muffler (2) onto the head pipe, support it with a stand, verify 2″ of insertion, and snug the clamp slightly (just enough to allow final adjustment later).
94
ISOLATOR
1
10 12 13 11
6. Slide the head pipe’s (1) hanger rod into the to the (rear) isolator. (If there is a front isolator, it may be removed
if desired.) Then attach the head pipe to the catalytic
converter flange using two 2″ bolts (10), lock washers (12), and nuts (11), and four flat washers (13). Lightly snug the fasteners (to allow final adjustment later).
9. Slip a 2-1/2″ clamp (9) over the muffler’s right outlet. Move the right over-axle pipe (4) into place, and slide its hanger rod into the isolator. Then slip the end of the pipe
into the muffler’s outlet, verify 2″ of insertion, and snug
the clamp slightly.
818147 Rev 01/03/23
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19 3
ISOLATOR
9
10. Slip a 2-1/2″ clamp (9) over the muffler’s left outlet. Move the left over-axle pipe (3) into place, slide its hanger rod into the isolator, and slip the end of the pipe into the muffler’s outlet. Verify 2″ of insertion, then snug the clamp slightly.
18 9
13. Adjust all components to give 1/2″ to 3/4″ clearance (about a finger’s width) around them, and allowing for suspension travel and vibration. When you are satisfied with the system’s clearance and fit, tighten all clamps. Use cable tie (19) to keep electrical and fluid lines away from exhaust components.
RECOMMENDED: Tack weld each slip-fit connection (approx. 1″ weld) for added security, then paint each weld with high-temp spray paint to protect against corrosion.
5
11. Slip a 2-1/2″ clamp (9) over the front of the left tailpipe (5), and move the pipe into place. Slip it onto the left over-axle pipe, slide its hanger rod into the rubber hanger
installed at Step 5, and install the two hanger keepers (18). Verify 3″ of insertion, and snug the clamp slightly.
7
6
9
Congratulations, the installation of your Flowmaster Force II performance exhaust system is complete!
KEEP THESE INSTRUCTIONS FOR FUTURE REFERENCE
Flowmaster maintains a highly-trained technical service department to answer your technical questions, provide additional product information and offer various recommendations.
12. Slip a 2-1/2″ clamp (9) over each rear exit pipe (6), and install each one on its tail pipe. Align each exit pipe as desired, verify 3″ of insertion, and snug each clamp slightly. Install a tip (7) on each rear exit pipe. Align each tip as desired, and tighten its clamp.
FLOWMASTER TECHNICAL SUPPORT: (866) 464-6553
818147 Rev 01/03/23
www.flowmastermufflers.com Technical Support (866) 464-6553
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