Exhaust Gasket - Rear

Replace the rear exhaust manifold gasket on the passenger side of the 302ci V8, requiring removal of the exhaust manifold and associated components.

Warnings

Tools required

Parts

• Rear (right side) exhaust manifold gasket × 1 — Use OEM specification for 302ci V8
• Exhaust manifold bolts (if corroded) × 8 — Use OEM specification
• Exhaust pipe flange gasket (donut gasket) × 1 — Use OEM specification
• Exhaust flange nuts × 2 — Use OEM specification

Preparation

1. Ensure engine and exhaust system are completely cold
2. Park vehicle on level surface and apply parking brake
3. Place wheel chocks behind front wheels
4. Disconnect negative battery cable
5. Spray all exhaust manifold bolts and exhaust pipe flange nuts with penetrating oil and allow to soak for 30 minutes minimum
6. Raise right side of vehicle and support securely on jack stands

Procedure

1. 1

   Disconnect exhaust pipe from manifold
   Working from underneath the vehicle, locate the exhaust pipe connection to the right side exhaust manifold. Remove the 2 nuts securing the exhaust pipe flange to the manifold collector. Support the exhaust pipe to prevent it from hanging on the remaining connections. Separate the pipe from the manifold and remove the old donut gasket.
2. 2

   Remove spark plug heat shields (if equipped)
   Some 1972 F-100 models have spark plug heat shields on the passenger side. If present, remove any clips or fasteners securing these shields to access the manifold bolts. Set shields aside for reinstallation.
3. 3

   Remove dipstick tube bracket
   The engine oil dipstick tube bracket typically attaches to one of the rear exhaust manifold bolts. Remove the bolt securing the dipstick tube bracket and carefully move the tube aside without bending it.
4. 4

   Remove exhaust manifold mounting bolts
   Remove all exhaust manifold mounting bolts (typically 6 on the 302 Windsor) working from front to back. Use a socket with extension to access the nuts through the tight spaces. If any studs break, use an extractor set to remove the remaining stud from the cylinder head. Keep nuts organized by position for reassembly.
5. 5

   Remove exhaust manifold
   Carefully pull the exhaust manifold away from the cylinder head. The manifold may be stuck to the head due to carbon buildup. Gently work it free, being careful not to damage the cylinder head sealing surface. Remove the manifold from the engine bay.
6. 6

   Remove old gasket material
   Using a gasket scraper and wire brush, thoroughly clean all old gasket material from both the cylinder head exhaust port faces and the exhaust manifold mating surface. Ensure all carbon deposits and debris are removed. The surfaces must be completely clean and flat for proper sealing. Inspect cylinder head surface for cracks or warping.
7. 7

   Inspect manifold and head
   Carefully inspect the exhaust manifold for cracks, especially around the bolt holes and between ports. Check the cylinder head exhaust port faces for cracks or damage. Minor surface imperfections can be addressed with careful cleaning, but cracks require component replacement.
8. 8

   Install new exhaust manifold gasket
   Position the new exhaust manifold gasket onto the cylinder head exhaust ports. Ensure the gasket is oriented correctly with any alignment tabs or markings facing the proper direction. The gasket should sit flat against the head without forcing.
9. 9

   Install exhaust manifold
   Carefully position the exhaust manifold over the studs, aligning it with the new gasket. Ensure the manifold seats evenly against the gasket without shifting it out of position. Thread all 8 manifold nuts by hand to hold the assembly in place.
10. 10

    Torque exhaust manifold bolts
    Torque the 8 exhaust manifold nuts in a spiral pattern starting from the center nuts and working outward. Tighten in two stages: first to 10 ft-lbs, then to final torque of 18-22 ft-lbs. This ensures even clamping pressure and prevents gasket distortion.
    ℹ️Torque specification is typical for 302ci V8 exhaust manifold bolts but should be verified against factory service manual.
11. 11

    Reinstall dipstick tube bracket
    Reattach the engine oil dipstick tube bracket to the appropriate exhaust manifold nut. Ensure the tube is properly positioned and not kinked or stressed.
12. 12

    Install new exhaust pipe gasket
    Place the new donut gasket onto the exhaust manifold collector outlet. Align the exhaust pipe flange with the manifold and start both flange nuts by hand.
13. 13

    Connect exhaust pipe to manifold
    Tighten the 2 exhaust pipe flange nuts evenly to 30 ft-lbs. Ensure the pipe is properly aligned and not stressed or pulled to one side. The connection should be secure without gaps.
    ℹ️Exhaust flange torque specification is typical for this application but should be verified.
14. 14

    Reinstall heat shields
    If heat shields were removed in step 2, reinstall them now with their original fasteners. Ensure they are positioned correctly to protect spark plug wires from exhaust heat.

Reassembly

1. Lower vehicle from jack stands
2. Reconnect negative battery cable
3. Double-check all fasteners are tightened to specification
4. Ensure no tools or parts are left in engine bay

Verification

• Start engine and allow to idle, listening for exhaust leaks at the manifold gasket or exhaust pipe connection
• Check for visible exhaust smoke or fumes escaping from the gasket area
• With engine at operating temperature, visually inspect all connections for leaks
• Rev engine to 2000 RPM and listen for any exhaust leak noise
• After test drive, re-check all exhaust manifold bolts and exhaust pipe flange nuts for tightness

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