Alternator

Remove and replace the alternator on a 2008 Dodge Viper 8.4L V10, including serpentine belt removal and electrical disconnection.

Warnings

Tools required

Parts

• Alternator × 1 — Use OEM specification or equivalent 160A alternator
• Serpentine belt (if worn or damaged) × 1 — Use OEM specification

Preparation

1. Park vehicle on level ground and engage parking brake.
2. Ensure engine is completely cool to the touch.
3. Open hood and secure with prop rod.
4. Photograph or sketch the serpentine belt routing for reinstallation reference.
5. Disconnect negative battery terminal and secure cable away from battery post.

Procedure

1. 1

   Disconnect battery negative terminal
   Using a 10mm wrench or battery terminal wrench, loosen the negative battery terminal clamp bolt. Remove the negative cable from the battery and position it away from the terminal to prevent accidental reconnection during the repair.
   Torque spec

   Battery Terminal Bolts8 Nm (6 lb-ft)
2. 2

   Release serpentine belt tension
   Locate the serpentine belt tensioner on the front of the engine. Using the correct size wrench or serpentine belt tool on the tensioner pulley bolt, rotate the tensioner in the direction indicated by the factory service manual to release belt tension. The tensioner is a spring-loaded automatic type; locate it on the front accessory drive of the engine (verify exact location against the belt routing diagram for this vehicle). Hold tension in the released position while removing the belt from one pulley.
   ⚠Control the tensioner carefully when releasing - it is spring-loaded and will snap back forcefully if released suddenly.
3. 3

   Remove serpentine belt
   With tension released, slip the serpentine belt off the alternator pulley or another accessible pulley. Slowly release the tensioner and allow it to return to its resting position. Remove the belt completely from all pulleys and withdraw from the engine bay. Inspect the belt for cracks, glazing, or excessive wear - replace if any damage is present.
4. 4

   Disconnect alternator electrical connections
   Locate the two electrical connections on the rear of the alternator. First, disconnect the main output wire by removing the terminal nut using a 13mm socket - this is a large wire with a ring terminal. Second, disconnect the field wire connector by pressing the release tab and pulling the connector straight off. Move both connections aside to provide clearance for alternator removal.
5. 5

   Remove alternator mounting bolts
   Remove the alternator upper mounting bolt using the correct size socket. This bolt secures the alternator to the mounting bracket. Next, remove the lower mounting bolt. Verify bolt sizes and mounting configuration against the factory service manual for this vehicle. Support the alternator with one hand while removing the final bolt to prevent it from falling.
   Torque spec

   Alternator Mounting Bolts50 Nm (37 lb-ft)

   Alternator Pivot Bolt25 Nm (18 lb-ft)
6. 6

   Remove alternator from engine bay
   With all fasteners and connections removed, carefully maneuver the alternator out of its mounting position. On the Viper V10, there is adequate clearance to lift the alternator up and out toward the passenger side fender. Rotate the alternator as needed to clear the engine accessories and frame rails. Set the old alternator aside on a clean work surface.
7. 7

   Prepare new alternator for installation
   Compare the new alternator to the old unit to verify correct pulley alignment, mounting bolt locations, and electrical connection types. If the pulley positions do not match, the pulley may need to be transferred from the old alternator. Clean the mounting surfaces on the engine block bracket with a wire brush or shop towel to ensure proper seating.
8. 8

   Install new alternator
   Position the new alternator into the mounting bracket, aligning the lower pivot hole first. Insert the lower pivot bolt finger-tight through the alternator and into the engine block bracket. Align the upper mounting hole and insert the upper bolt finger-tight. Do not fully tighten bolts at this stage to allow for alignment adjustment.
   Torque spec

   Alternator Mounting Bolts50 Nm (37 lb-ft)

   Alternator Pivot Bolt25 Nm (18 lb-ft)
9. 9

   Torque alternator mounting bolts
   Using a torque wrench and the correct size socket, torque the alternator mounting bolts to the factory-specified value listed in the service manual for this vehicle. Verify the alternator is secure and does not move in the bracket after torquing. Verify the alternator is secure and does not move in the bracket after torquing.
   Torque spec

   Alternator Mounting Bolts50 Nm (37 lb-ft)

   Alternator Pivot Bolt25 Nm (18 lb-ft)
10. 10

    Reconnect alternator electrical connections
    Reconnect the field wire connector to the alternator by pushing it onto the terminal until the locking tab clicks into place - tug gently to verify it is seated. Install the main output wire ring terminal onto the alternator output stud and secure with the terminal nut. Torque the output terminal nut to the factory-specified value using the correct size socket - do not overtighten as the stud can break.
11. 11

    Install serpentine belt
    Following the belt routing diagram or your reference photo, route the new or existing serpentine belt around all pulleys except the alternator pulley (leave this for last as it's easiest to access). Using the 18mm wrench or belt tool, rotate the tensioner clockwise to release tension and slip the belt onto the alternator pulley. Carefully release the tensioner to apply proper belt tension. Verify the belt is centered on all pulley grooves and not riding on any pulley edges.
12. 12

    Reconnect battery negative terminal
    Position the negative battery cable onto the negative battery post. Using a 10mm wrench or battery terminal wrench, tighten the terminal clamp bolt to the factory-specified value (typically around 8 Nm / 6 lb-ft). Ensure the connection is secure but do not overtighten. Ensure the connection is secure but do not overtighten as this can damage the battery post.
    Torque spec

    Battery Terminal Bolts8 Nm (6 lb-ft)

Reassembly

1. Verify all electrical connections at the alternator are secure and properly seated.
2. Check that the serpentine belt is properly routed and seated in all pulley grooves.
3. Ensure no tools or parts have been left in the engine bay.

Verification

• Start the engine and verify it runs smoothly without unusual noises from the alternator or belt area.
• With the engine running, turn on electrical accessories (headlights, A/C, radio) and verify they operate normally.
• Using a multimeter, measure battery voltage with engine running - should read 13.5-14.5 volts, indicating proper alternator charging.
• Observe the alternator warning light on the instrument cluster - it should illuminate with ignition on/engine off, then extinguish immediately when the engine starts.
• Listen for any belt squealing or bearing noise from the alternator while the engine is running.
• Visually inspect the serpentine belt while the engine is running to confirm it tracks properly in all pulley grooves without slipping or walking off the pulleys.

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