This procedure covers the removal and replacement of the exhaust resonator on a 2015-2020 Ford F-150 with the 3.5L EcoBoost V6 engine.

Warnings

Tools required

Parts

• Exhaust resonator assembly × 1 — Use OEM specification or aftermarket equivalent
• Exhaust flange gasket × 2 — FL3Z-5A231-A or equivalent
• Exhaust clamp (if replacing clamp-type connections) × 2 — Use OEM specification
• Rubber exhaust hangers (if damaged) × 2 — Inspect and replace as needed

Preparation

1. Park vehicle on level surface and allow exhaust system to cool completely (minimum 2 hours after last operation)
2. Engage parking brake and chock rear wheels
3. Raise vehicle on lift or securely support on jack stands at manufacturer-specified lift points
4. Spray all exhaust fasteners and clamps with penetrating oil and allow to soak for 15-20 minutes
5. Locate the resonator assembly between the catalytic converters and muffler, typically positioned mid-chassis
6. Visually inspect the resonator mounting configuration (flange bolts or clamps) to confirm hardware needed

Procedure

1. 1

   Support the exhaust system
   Position a jack or support stand under the muffler section to support the weight of the exhaust system aft of the resonator. This prevents the exhaust from hanging on the catalytic converters when the resonator is disconnected.
2. 2

   Disconnect forward flange connection
   Locate the flange connection between the catalytic converter outlet and the resonator inlet. Remove the two flange bolts using a 15mm socket. If bolts are seized, apply additional penetrating oil and use a breaker bar. Separate the flange connection and remove the old gasket.
   ⚠Flange bolts may break if excessive force is applied to corroded fasteners. Heat or bolt extractors may be necessary for severely corroded hardware.
   Torque spec

   Flange Bolts45 Nm (33 lb-ft)
3. 3

   Disconnect rear connection
   At the rear of the resonator, identify the connection type to the intermediate pipe or muffler inlet. For flange-type connections, remove the flange bolts using a 15mm socket. For clamp-type connections, loosen the clamp bolts using a 13mm socket and remove the clamp assembly. Separate the connection.
   Torque spec

   Flange Bolts45 Nm (33 lb-ft)

   Exhaust Clamps55 Nm (41 lb-ft)
4. 4

   Remove exhaust hanger connections
   Locate the rubber exhaust hangers supporting the resonator (typically two hangers). Use a pry bar or exhaust hanger removal tool to carefully pry the hanger isolators off the mounting studs. Work the rubber grommets off the hangers by pushing the exhaust pipe toward the hanger stud while prying.
5. 5

   Remove resonator assembly
   With all connections and hangers disconnected, carefully lower and remove the resonator assembly from the vehicle. Maneuver it past any crossmembers or suspension components. Note the orientation and routing for installation of the replacement unit.
6. 6

   Clean and inspect mounting points
   Use a wire brush to clean all flange mating surfaces, removing carbon buildup, old gasket material, and corrosion. Inspect exhaust hangers for cracks or excessive wear; replace if rubber is torn or deteriorated. Check flange surfaces for warping or damage.
7. 7

   Position new resonator
   Position the new resonator assembly under the vehicle, aligning it with the forward and rear connection points. Ensure proper orientation matches the original configuration. Loosely install the resonator onto the exhaust hangers first to help support the assembly during connection.
8. 8

   Install forward flange connection
   Install a new exhaust flange gasket at the forward connection between the catalytic converter and resonator inlet. Align the flange bolt holes and install the flange bolts finger-tight. Do not torque at this stage to allow for alignment adjustments.
9. 9

   Install rear connection
   At the rear connection, install a new flange gasket (for flange-type) or position the clamp (for clamp-type). Align the connection and install fasteners finger-tight. Ensure proper alignment with no binding or stress on the exhaust system.
10. 10

    Align exhaust system
    Verify the entire exhaust system has adequate clearance from the chassis, fuel tank, driveshaft, and suspension components. Adjust the position of the resonator as needed to maintain minimum 1/2 inch clearance from all components. Ensure hangers are properly seated on their mounting studs.
    ⚠Inadequate clearance can cause rattles, vibration, and potential damage to exhaust or chassis components during vehicle operation.
11. 11

    Torque forward flange bolts
    Using a torque wrench, tighten the forward flange bolts to specification in a cross pattern to ensure even seating of the gasket and prevent exhaust leaks.
    Torque spec

    Flange Bolts45 Nm (33 lb-ft)
12. 12

    Torque rear connection
    Torque the rear connection fasteners to specification. For flange-type connections, torque flange bolts in a cross pattern. For clamp-type connections, torque the clamp bolts evenly to compress the clamp uniformly around the joint.
    Torque spec

    Flange Bolts45 Nm (33 lb-ft)

    Exhaust Clamps55 Nm (41 lb-ft)
13. 13

    Final inspection
    Remove the support from under the muffler. Perform a final visual inspection of all connections, ensuring all fasteners are tight and the exhaust system has proper clearance. Verify exhaust hangers are fully seated and supporting the system without excessive stress.

Reassembly

1. Torque all flange bolts to 45 Nm (33 lb-ft) in a cross pattern
2. Torque all exhaust clamps (if applicable) to 55 Nm (41 lb-ft)
3. Verify minimum 1/2 inch clearance between exhaust components and chassis/suspension
4. Ensure all rubber exhaust hangers are properly seated and not torn or damaged

Verification

• Lower the vehicle to the ground
• Start the engine and allow it to idle while listening for exhaust leaks at the resonator connections
• Check for unusual vibrations or rattles from the exhaust system
• Perform a brief test drive and listen for any exhaust leaks, rattles, or contact with chassis components
• After test drive, raise vehicle and visually inspect all connections for signs of leakage (soot marks)
• Verify exhaust system maintains proper clearance and alignment after heat cycling

More procedures for this vehicle