Cooling Fan Assembly

Remove and replace the engine cooling fan assembly on a 2008 Dodge Viper, including the electric fan motor, fan blade, and shroud assembly.

Warnings

Tools required

Parts

• Cooling fan assembly (fan motor, blade, and shroud) × 1 — Use OEM specification
• Fan wiring harness connector (if damaged) × 1 — Use OEM specification

Fluids

• Mopar HOAT coolant 50/50 — 2 qt

Preparation

1. Ensure engine is completely cold to the touch (wait at least 2 hours after last operation).
2. Open hood and secure in upright position.
3. Disconnect negative battery cable and secure away from terminal.
4. Place drain pan under radiator if planning to drain coolant (optional but recommended for cleaner work area).
5. Photograph or note fan wiring connector orientation before disconnection.

Procedure

1. 1

   Remove upper radiator hose
   Locate the upper radiator hose connection at the radiator inlet (verify exact location for the 2008 Viper radiator). Squeeze or release the spring clamp using pliers and slide it back away from the radiator neck approximately 2 inches. Gently twist and pull the hose off the radiator inlet. Be prepared for coolant spillage; direct into drain pan. Tuck hose out of the work area.
2. 2

   Disconnect fan electrical connector
   Locate the fan motor electrical connector on the fan shroud (typically driver side or bottom of shroud). Press the locking tab and pull the connector apart. The connector may have a secondary safety lock that slides out first—check for a small sliding tab before attempting to separate the main connector. Allow the harness to hang free or secure it away from the fan area.
3. 3

   Remove upper fan shroud fasteners
   Remove the upper mounting fasteners securing the fan shroud to the radiator support. These fasteners (count and type to be verified against factory documentation) are typically located along the top edge of the shroud as bolts and/or clips. Check for fasteners at each upper corner and center positions. Note fastener locations as they may differ in length or have spacers.
4. 4

   Remove lower fan shroud fasteners
   Working from above or below the vehicle (depending on access), locate and remove the lower mounting fasteners securing the fan shroud. These typically include lower fasteners or tabs (count and type to be verified against factory documentation) that engage slots in the radiator lower support. The shroud may have lower tangs that simply hook into the radiator frame—check for these before forcing removal.
5. 5

   Lift fan assembly from engine bay
   With all fasteners removed and electrical connection disconnected, carefully lift the entire fan assembly (shroud, motor, and blade as one unit) straight up and out of the engine compartment. The assembly is positioned between the radiator and engine block with limited clearance. Tilt the top of the assembly slightly toward the engine as you lift to clear the radiator, then lift straight up. The assembly weighs approximately 15-20 pounds. Ensure the fan blade clears all hoses and the radiator core during removal.
6. 6

   Separate fan motor from shroud (if replacing motor only)
   If replacing only the fan motor and not the entire assembly, place the removed assembly on a clean work surface. Remove the bolts securing the fan motor to the shroud mounting bracket (exact count to be verified against factory documentation). These bolts pass through the motor housing into the bracket. Note the orientation of the motor and any spacers or rubber isolators. Carefully pull the motor with attached fan blade away from the shroud.
7. 7

   Remove fan blade from motor (if needed)
   If replacing the fan blade separately, verify the blade retention method in the factory service manual (retaining nut, clip, or integral to motor). If a center retaining nut is used, hold the motor shaft stationary (use a wrench on the flat sections if provided) and remove the nut, confirming thread direction before applying force. Pull the fan blade off the motor shaft, noting the orientation and any alignment keys or flat spots on the shaft.
8. 8

   Install new fan blade to motor (if replaced)
   Align the new fan blade with the motor shaft, matching any keyways or flat spots. The blade has a specific orientation—curved blades should pull air through the radiator toward the engine (verify direction arrow if marked on blade). Thread the retaining nut onto the shaft and tighten securely. Hold the motor shaft to prevent rotation while tightening the nut.
9. 9

   Install motor to shroud (if separated)
   Position the fan motor (with blade attached) into the shroud mounting bracket, aligning the motor mounting holes with the bracket holes. Ensure any rubber isolators or spacers are properly positioned. Install the 3 or 4 mounting bolts and tighten in a cross pattern to ensure even seating. Verify the fan blade rotates freely within the shroud without contact.
10. 10

    Install fan assembly into vehicle
    Lower the complete fan assembly (shroud, motor, and blade) into the engine bay. Position it between the radiator and engine, ensuring the lower tangs or mounting points align with the radiator frame. The shroud should sit flush against the radiator with even gaps around the perimeter. Tilt as needed to clear obstructions during installation, reversing the removal motion.
11. 11

    Install fan shroud fasteners
    Install and hand-tighten all upper mounting fasteners first (typically 4 bolts along the top edge). Ensure the shroud is properly positioned before tightening. Then install the lower mounting fasteners or engage the lower mounting tabs. Tighten all fasteners securely in a cross pattern, but do not overtighten plastic shroud mounting points.
12. 12

    Reconnect electrical connector and radiator hose
    Reconnect the fan motor electrical connector, ensuring it clicks fully into place and any secondary lock engages. Tug gently to verify connection. Reinstall the upper radiator hose onto the radiator inlet neck, pushing it fully onto the fitting. Slide the spring clamp back into position over the hose end, positioning it approximately 1/2 inch from the end of the fitting.
13. 13

    Refill coolant and check level
    If coolant was drained or lost during the procedure, add the factory-specified Mopar coolant (mixed 50/50 with distilled water; verify the exact coolant type for the 2008 Viper in the service manual) to the radiator until full. Also check and fill the coolant overflow reservoir to the COLD FULL mark. Add approximately 1-2 quarts as needed to replace lost coolant. Do not overfill.
14. 14

    Reconnect battery and test fan operation
    Reconnect the negative battery cable. Start the engine and allow it to reach operating temperature (approximately 195-210°F). The cooling fan should activate automatically when the engine reaches normal operating temperature. Observe the fan for proper rotation direction (pulling air through the radiator), smooth operation without wobble or noise, and proper cycling on and off. Turn on the air conditioning—the fan should activate immediately if not already running.

Reassembly

1. Reassembly is covered in the installation steps above, following reverse order of disassembly.
2. Ensure all coolant hose clamps are properly positioned and secure before starting engine.
3. Double-check fan electrical connector engagement before testing operation.

Verification

• Start engine and verify cooling fan activates when engine reaches operating temperature (195-210°F on gauge).
• Turn air conditioning on—fan should activate immediately if not already running.
• Listen for unusual noises from fan motor or blade contact with shroud—operation should be smooth and quiet.
• Check for coolant leaks around upper radiator hose connection after engine reaches temperature.
• Verify coolant level in overflow reservoir remains at COLD FULL mark after engine cools.
• Observe fan blade for wobble or imbalance during operation—blade should spin true without visible runout.

Related trouble codes on this vehicle

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