Engine Mount - Torque Axis

Replace the torque axis (dog bone) engine mount on a 2008 Dodge Viper 8.4L V10, which controls longitudinal engine movement and vibration transfer to the chassis.

Warnings

Tools required

Parts

• Torque axis engine mount × 1 — Use OEM specification

Preparation

1. Park vehicle on level surface and engage parking brake
2. Allow engine and exhaust system to cool completely
3. Disconnect negative battery cable
4. Raise front of vehicle and support securely on jack stands at manufacturer lift points
5. Remove engine belly pan if equipped to access engine mount area

Procedure

1. 1

   Locate the torque axis mount
   The torque axis mount is located between the engine and the vehicle frame/subframe bracket. Verify the exact mount style, location, and orientation against the factory service manual for the 2008 Viper before removal, and inspect the mount for visible damage, cracking, or separation. Inspect the mount for visible damage, cracking, or separation before removal.
2. 2

   Support the engine
   Position an engine support fixture across the engine bay and attach it securely to engine lifting points, or position a transmission jack with a wide wood block under the oil pan. Apply slight upward pressure to take the load off the torque mount, but do not lift the engine significantly. The goal is to relieve tension on the mount fasteners.
   ⚠️Ensure the engine support is stable and secure before proceeding. The engine weighs over 700 pounds and must be fully supported.
3. 3

   Apply penetrating lubricant
   Spray all torque mount fasteners (both engine-side and chassis-side) with penetrating lubricant. Allow 10-15 minutes for penetration. This mount is exposed to road spray and heat, and fasteners are typically corroded.
4. 4

   Remove engine-side mount fastener
   Locate the bolt securing the torque mount to the engine bracket (typically on the front of the engine block). Using a socket and ratchet or breaker bar, remove the bolt that passes through the mount bushing. This is typically a single large bolt. Support the mount as you remove the last threads to prevent it from dropping. Note: Bolt size and torque per 2008 Viper factory service manual — verify before use
5. 5

   Remove chassis-side mount fasteners
   Locate the fasteners securing the torque mount to the subframe/crossmember bracket. Remove the chassis-side bolts (count per factory service manual) securing the mount to the chassis bracket. The mount should now be free to remove from the vehicle.
6. 6

   Remove torque mount
   Withdraw the torque mount from between the engine and chassis. You may need to slightly adjust engine support height or use a pry bar to maneuver the mount out of position. Inspect the mounting brackets on both the engine and chassis for damage, cracks, or elongated bolt holes.
7. 7

   Clean mounting surfaces
   Use a wire brush to clean the mounting surfaces on both the engine bracket and chassis bracket. Remove any rust, corrosion, or debris. Inspect threads in any threaded mounting holes and clean or chase with a tap if necessary. Clean the bolt threads with a wire brush.
8. 8

   Position new torque mount
   Position the new torque mount between the engine and chassis brackets. Align the mount bushing with the engine bracket first. You may need to adjust the engine support slightly to align the mounting holes. The mount orientation is critical—ensure the mount is not installed backwards or upside down.
9. 9

   Install engine-side fastener
   Insert the bolt through the engine bracket and torque mount bushing. Thread the bolt by hand to ensure proper alignment. Snug the bolt but do not fully torque yet—the mount should be torqued with the vehicle at ride height and the engine under its natural load.
10. 10

    Install chassis-side fasteners
    Install the 2 bolts securing the torque mount to the chassis bracket. Thread bolts by hand first to verify alignment. Snug the bolts but do not fully torque yet.
11. 11

    Lower vehicle to ride height
    Carefully remove the engine support fixture or lower the transmission jack to allow the engine to settle into its natural position. Lower the vehicle from the jack stands so the suspension is at normal ride height. This ensures the mount is torqued without pre-load or binding.
12. 12

    Torque mount fasteners
    With the vehicle at ride height, torque the engine-side and chassis-side bolts to the factory service manual specifications for the 2008 Viper 8.4L V10. Do not rely on generic values—verify exact torque and any specified sequence in the FSM before final tightening.

Reassembly

1. Reinstall engine belly pan if removed
2. Reconnect negative battery cable
3. Clear any stored diagnostic codes if the battery was disconnected for extended period

Verification

• Start the engine and verify no abnormal vibration at idle
• Visually inspect the torque mount for proper alignment and no contact with surrounding components
• Test drive the vehicle and verify smooth acceleration without excessive engine movement or vibration
• Perform a gentle acceleration test to ensure the mount properly controls engine torque reaction

Related trouble codes on this vehicle

Codes that commonly send this job to the bay — tap one for symptoms, causes, and diagnostic steps.

Chasing one of these codes and not sure which part is guilty? Ask a master mechanic about YOUR car →

More procedures for this vehicle