Radiator Hose - Lower

Remove and replace the lower radiator hose on a 2008 Dodge Viper 8.4L V10, including coolant drain and refill procedures.

Warnings

Tools required

Parts

• Lower radiator hose × 1 — Use OEM specification
• Hose clamp (radiator end) × 1 — Spring-type or worm-drive depending on original equipment
• Hose clamp (engine end) × 1 — Spring-type or worm-drive depending on original equipment

Fluids

• Mopar HOAT coolant 50/50 — 4 qt

Preparation

1. Ensure engine is completely cold to the touch
2. Park vehicle on level surface and apply parking brake
3. Place drain pan under radiator drain plug location at lower driver side of radiator
4. Remove radiator cap slowly to release any residual pressure

Procedure

1. 1

   Drain coolant from radiator
   Open the radiator petcock drain valve located at the lower corner of the radiator by turning counterclockwise. Allow coolant to drain into the drain pan. Once flow stops, close the petcock. You do not need to drain the entire cooling system, just enough to drop the level below the lower hose connection point.
2. 2

   Access lower radiator hose at radiator end
   Locate the lower radiator hose connection at the bottom passenger side of the radiator. The hose runs from the radiator outlet down and toward the passenger side of the engine block. Inspect the hose clamp type at the radiator connection (spring-type or worm-drive screw clamp).
3. 3

   Remove radiator-end hose clamp
   If equipped with a spring-type clamp, use hose clamp pliers to compress the clamp tabs and slide the clamp back along the hose away from the radiator neck. If equipped with a worm-drive screw clamp, use a flat-blade screwdriver to loosen the screw and slide the clamp back along the hose. Position the clamp at least 3 inches back from the radiator connection.
4. 4

   Disconnect hose from radiator
   Twist the hose back and forth while pulling to break the seal between the hose and radiator outlet neck. Pull the hose straight off the radiator outlet. Expect additional coolant to drain from the hose and radiator; have shop towels ready. Inspect the radiator outlet neck for damage or corrosion.
5. 5

   Access lower radiator hose at engine end
   Follow the lower radiator hose to its connection point at the water pump inlet on the front of the engine. Access may require reaching down between the engine and frame rail. Access may require reaching down between the engine and frame rail.
6. 6

   Remove engine-end hose clamp
   Using the appropriate tool for the clamp type (hose clamp pliers for spring-type or screwdriver for worm-drive), release the clamp and slide it back along the hose away from the water pump connection. Position the clamp at least 3 inches back from the fitting.
7. 7

   Disconnect hose from engine and remove
   Twist the hose back and forth while pulling to break the seal between the hose and water pump fitting. Pull the hose off the fitting. Remove the lower radiator hose from the engine bay. Drain any remaining coolant from the hose into the drain pan. Inspect both connection fittings on the radiator and water pump for corrosion, damage, or debris.
8. 8

   Prepare new lower radiator hose
   Compare the new lower radiator hose to the old hose to verify correct length and bend configuration. If reusing hose clamps, inspect them for corrosion or damage and replace if necessary. If clamps are spring-type, position one clamp on each end of the new hose, oriented so the tabs face the direction accessible for future service. If worm-drive type, slide clamps onto hose with screw accessible.
9. 9

   Install hose onto water pump fitting
   Route the new lower radiator hose into position. Install the engine end of the hose onto the water pump outlet fitting first, pushing firmly until the hose is fully seated against the fitting stop ridge. The hose should slide on approximately 1.5 to 2 inches onto the fitting. Ensure the hose is routed without kinks or sharp bends.
10. 10

    Secure engine-end hose clamp
    Slide the hose clamp forward to position it approximately 0.5 inches from the end of the fitting, centered over the fitting bead. For spring-type clamps, compress with hose clamp pliers and position securely over the connection. For worm-drive clamps, tighten the screw until the clamp is snug but not overtightened (finger-tight plus 1/4 turn).
11. 11

    Install hose onto radiator outlet
    Push the radiator end of the lower hose firmly onto the radiator outlet neck until fully seated against the neck stop ridge. Verify the hose routing does not contact any sharp edges, the exhaust system, or moving components. The hose should follow a smooth path without twisting.
12. 12

    Secure radiator-end hose clamp
    Slide the hose clamp forward to position it approximately 0.5 inches from the end of the radiator neck, centered over the neck bead. Secure the clamp using the same method as the engine end. Verify both clamps are properly positioned and secure.
13. 13

    Refill cooling system
    Using a funnel, slowly pour Mopar HOAT 50/50 coolant mixture into the cooling system through the designated fill/pressure cap opening. Fill until coolant level reaches the bottom of the filler neck. Allow time for coolant to flow through the system and air to escape. Add additional coolant as the level drops. Once full, install the radiator cap.
14. 14

    Burp cooling system and check for leaks
    Start the engine and allow it to reach normal operating temperature with the heater set to maximum heat. Monitor the temperature gauge to ensure it remains in the normal range. As the thermostat opens, the coolant level may drop; add additional coolant as needed. After the engine reaches operating temperature, turn off the engine and allow it to cool for 15 minutes. Check the radiator coolant level and top off if necessary. Inspect both hose connections for any signs of coolant leaks.

Reassembly

1. No disassembly of other components required for this procedure

Verification

• Visually inspect both hose clamp locations for any signs of coolant seepage or wetness
• Verify coolant level in radiator is at the bottom of the filler neck when cold
• Start engine and observe temperature gauge reaches normal operating range without overheating
• Check that heater produces hot air, confirming coolant circulation
• After test drive, recheck all hose connections for leaks and verify coolant level has not dropped

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