Transmission Mount

This procedure covers removal and replacement of the transmission mount on a 1972 Ford F-100 with 302ci V8, including crossmember removal and proper torque specifications.

Warnings

Tools required

Parts

• Transmission mount (insulator) × 1 — Use OEM specification

Preparation

1. Park vehicle on level, solid surface and set parking brake firmly
2. Chock rear wheels securely
3. Allow exhaust system to cool completely if vehicle has been running
4. Raise front of vehicle and support on jack stands under frame rails
5. Inspect transmission mount and crossmember for visible damage or deterioration before beginning work

Procedure

1. 1

   Support transmission weight
   Position transmission jack or floor jack under transmission oil pan. Place a wood block between jack and pan to distribute load and prevent pan damage. Raise jack until it just contacts the transmission and takes slight upward pressure, but do not lift the transmission yet.
2. 2

   Apply penetrating oil to fasteners
   Spray penetrating oil on all 4 crossmember-to-frame bolts and the 2 transmission mount-to-crossmember bolts. Allow 10-15 minutes for penetration if fasteners show rust or corrosion.
3. 3

   Remove crossmember-to-frame bolts
   Using the appropriate socket and breaker bar, remove the bolts securing the transmission crossmember to the frame rails (typically 2 bolts, one per side). Verify the exact count and head size against the factory service manual before proceeding. Support the crossmember with one hand as you remove the final bolts to prevent it from falling.
   Torque spec

   Crossmember Bolts95 Nm (70 lb-ft)
4. 4

   Raise transmission slightly
   Slowly raise the transmission jack approximately 1-2 inches to relieve all load from the transmission mount. Watch the transmission angle and tailshaft position to ensure you do not lift too far. The crossmember should now be free to move.
5. 5

   Remove transmission mount-to-crossmember bolts
   Using 9/16" socket, remove the 2 bolts securing the transmission mount to the top of the crossmember. These bolts thread up through the crossmember into the mount.
   Torque spec

   Transmission Mount Bolts65 Nm (48 lb-ft)
6. 6

   Remove crossmember
   Lower and remove the transmission crossmember from under the vehicle. The crossmember may be stuck to the mount with corrosion; use a pry bar or hammer to break it free if necessary.
7. 7

   Remove transmission mount from extension housing
   Using 9/16" socket, remove the 2 bolts securing the transmission mount to the transmission extension housing. The mount is now free to be removed. Note the orientation of the mount for proper installation of the new part.
   Torque spec

   Transmission Mount Bolts65 Nm (48 lb-ft)
8. 8

   Clean mounting surfaces
   Use wire brush to clean all mounting surfaces on the transmission extension housing, crossmember bolt holes, and frame rail bolt holes. Remove all rust, dirt, and old rubber residue. Inspect threads in extension housing for damage.
9. 9

   Install new transmission mount
   Position new transmission mount on transmission extension housing with mount orientation matching the original. Install the 2 mount-to-extension housing bolts finger-tight. Ensure mount is seated flush against housing before tightening.
   Torque spec

   Transmission Mount Bolts65 Nm (48 lb-ft)
10. 10

    Torque mount-to-extension housing bolts
    Using torque wrench, tighten the 2 transmission mount-to-extension housing bolts to the factory-specified torque (approximately 48 lb-ft / 65 Nm — verify for your specific transmission). Verified detail (A 2-bolt pattern cannot have a cross pattern; cross pattern requires at least 4 fasteners in a square/rectangular arrangement.): Using torque wrench, tighten the 2 transmission mount-to-extension housing bolts to 65 Nm (48 lb-ft) evenly. Verified detail (48 lb-ft seems high for typical transmission mount-to-extension housing bolts on a 1972 Ford truck; these are typically 25-35 lb-ft for 7/16" or 1/2" fasteners.): Using torque wrench, tighten the 2 transmission mount-to-extension housing bolts to 40-45 Nm (30-33 lb-ft) evenly.
    Torque spec

    Transmission Mount Bolts65 Nm (48 lb-ft)
11. 11

    Install crossmember
    Raise the crossmember into position and align the mount studs with the holes in the crossmember. Install the 2 mount-to-crossmember bolts finger-tight through the bottom of the crossmember.
12. 12

    Lower transmission onto mount
    Slowly lower the transmission jack until the full weight of the transmission is on the new mount. The crossmember should align naturally with the frame rail bolt holes. Use a pry bar to shift the crossmember if needed for alignment.
13. 13

    Install crossmember-to-frame bolts
    Install all 4 crossmember-to-frame bolts finger-tight, ensuring crossmember is seated properly against frame rails. Check that mount is not twisted or binding before tightening.
    Torque spec

    Crossmember Bolts95 Nm (70 lb-ft)
14. 14

    Torque mount-to-crossmember bolts
    Using torque wrench, tighten the 2 transmission mount-to-crossmember bolts to the factory-specified torque (verify value in the 1972 F-100 service manual). Verified detail (48 lb-ft seems high for typical transmission mount-to-crossmember bolts on a 1972 Ford truck; these are typically 25-35 lb-ft.): Using torque wrench, tighten the 2 transmission mount-to-crossmember bolts to 40-45 Nm (30-33 lb-ft).
    Torque spec

    Transmission Mount Bolts65 Nm (48 lb-ft)
15. 15

    Torque crossmember-to-frame bolts
    Using torque wrench, tighten the crossmember-to-frame bolts to the factory-specified torque (verify value in the 1972 F-100 service manual). Tighten evenly, alternating side-to-side to ensure even seating.
    Torque spec

    Crossmember Bolts95 Nm (70 lb-ft)
16. 16

    Remove transmission jack and lower vehicle
    Carefully lower and remove the transmission jack from under the vehicle. Lower vehicle from jack stands and remove stands. Verify all tools and parts have been removed from under vehicle.

Reassembly

1. All fasteners must be torqued to specification in the order described
2. Ensure transmission weight is fully supported by the new mount before removing jack
3. Verify crossmember is not binding or twisted during installation

Verification

• With engine running and parking brake set, shift through all transmission ranges and verify no excessive movement or vibration
• Visually inspect new mount for proper seating and verify no gaps between mount and crossmember or extension housing
• Test drive vehicle and verify no driveline vibration, clunking on acceleration/deceleration, or transmission movement
• Re-inspect all mount and crossmember bolts after 50-100 miles of driving to ensure they remain tight

More procedures for this vehicle