Coolant Reservoir

Remove and replace the coolant reservoir on a 2005 Dodge Viper 8.3L V10, including draining coolant, disconnecting hoses, and refilling the cooling system.

Warnings

Tools required

Parts

• Coolant reservoir × 1 — Use OEM specification
• Reservoir cap × 1 — Use OEM specification if damaged

Fluids

• Zerex G-05 HOAT 50/50 coolant — 2 qt

Preparation

1. Ensure the engine is completely cold (minimum 2 hours after last operation).
2. Park the vehicle on level ground and engage the parking brake.
3. Place a drain pan beneath the radiator drain location.
4. Open the hood and locate the coolant reservoir on the driver's side of the engine bay.

Procedure

1. 1

   Partially drain the cooling system
   Slowly remove the coolant reservoir cap by turning counterclockwise to release any residual pressure. Locate the radiator drain petcock at the bottom of the radiator; if no accessible petcock is present, drain by loosening the lower radiator hose. Verify the exact drain location against the 2005 Viper service manual. Open the petcock and drain coolant into the drain pan until the level is below the reservoir hose connections. The amount required depends on reservoir height in the system; verify against the 2005 Viper service manual. Close the drain petcock hand-tight once the level is below the reservoir.
   Torque spec

   Drain Petcock7 Nm (5 lb-ft)
2. 2

   Disconnect the lower hose from reservoir
   Locate the lower coolant hose connecting the reservoir to the radiator. Using a flathead screwdriver or hose clamp pliers, loosen the hose clamp by turning counterclockwise or squeezing the clamp tabs. Slide the clamp away from the reservoir connection point. Twist and pull the hose off the reservoir nipple. Allow any remaining coolant to drain into your drain pan.
   Torque spec

   Hose Clamps4 Nm (3 lb-ft)
3. 3

   Disconnect the upper overflow hose
   Locate the upper overflow hose that connects to the top or side of the reservoir. This smaller diameter hose typically connects to the radiator filler neck or a coolant line. Loosen the hose clamp and slide it away from the reservoir connection. Remove the hose from the reservoir.
   Torque spec

   Hose Clamps4 Nm (3 lb-ft)
4. 4

   Remove reservoir mounting fasteners
   Identify the reservoir mounting bolts securing the reservoir to the inner fender or mounting bracket. The reservoir mounting fastener count and location must be verified against the 2005 Viper service manual. Remove all mounting fasteners using the appropriate socket, supporting the reservoir as you remove the final fastener. Support the reservoir with one hand as you remove the final fastener.
   Torque spec

   Reservoir Mounting Bolts8 Nm (6 lb-ft)
5. 5

   Remove the coolant reservoir
   Lift the coolant reservoir up and out of the engine bay. Tip the reservoir to drain any remaining coolant into your drain pan. Inspect the mounting area for corrosion or damage. Clean the mounting bracket and hose connection points with a shop rag.
6. 6

   Prepare and install new reservoir
   Inspect the new reservoir for shipping damage and ensure all connection points are clean. If reusing hose clamps, verify they are not damaged or excessively corroded; replace if necessary. Position the new reservoir into the mounting location, aligning the mounting holes with the bracket.
7. 7

   Install reservoir mounting fasteners
   Thread both reservoir mounting bolts by hand to prevent cross-threading. Once both bolts are started, tighten them evenly in an alternating pattern to the factory-specified torque (verify against the 2005 Viper service manual; typical small bracket bolts are low torque and easily stripped in a plastic reservoir). Ensure the reservoir is secure and properly seated against the mounting bracket.
   Torque spec

   Reservoir Mounting Bolts8 Nm (6 lb-ft)
8. 8

   Reconnect coolant hoses
   Connect the upper overflow hose to the reservoir first, pushing it fully onto the nipple until it seats. Position the hose clamp over the connection point and tighten to the specified torque. Connect the lower coolant hose to the reservoir, ensuring it is fully seated, then position and tighten the hose clamp to specification.
   Torque spec

   Hose Clamps4 Nm (3 lb-ft)
9. 9

   Refill the cooling system
   Using a funnel, add the OEM-specified coolant (verify type — G-05 HOAT or Mopar-spec) as a 50/50 mixture to the reservoir until the level reaches the FULL COLD mark on the reservoir. Add additional coolant through the radiator fill neck until the radiator is full. Install the radiator cap and reservoir cap. You should only need to replace the coolant drained plus any spillage. Verify the total cooling system capacity against the 2005 Viper service manual before topping off.
10. 10

    Bleed air from the cooling system
    Start the engine and allow it to warm up to operating temperature with the heater set to maximum heat. Monitor the coolant level in the reservoir as the thermostat opens and air purges from the system. Add coolant as needed to maintain the proper level. Allow the engine to run until the cooling fans cycle on and off at least once. Shut off the engine and allow it to cool, then recheck the coolant level and top off to the FULL COLD mark if necessary.

Reassembly

1. Installation is performed in reverse order of removal, following steps 6-10.
2. Ensure all hose clamps are properly tightened to prevent coolant leaks.
3. Double-check that both mounting bolts are torqued to specification to prevent reservoir movement or cracking.

Verification

• With the engine cold, verify the coolant level is at the FULL COLD mark on the reservoir.
• Start the engine and visually inspect all hose connections for leaks while the engine warms up.
• Verify that the cooling fans cycle on and off properly and the temperature gauge reads in the normal range.
• After the engine cools completely, recheck the coolant level and top off if necessary.
• Check for coolant leaks on the ground beneath the vehicle after the first drive cycle.

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