AC Compressor Oil Add

This procedure adds oil to the AC compressor system on a 2008 Dodge Viper with 8.4L V10 engine to maintain proper lubrication during service or after component replacement.

Warnings

Tools required

Parts

• PAG 46 compressor oil × 1 — Use Mopar PAG 46 or equivalent R-134a compatible

Fluids

• PAG 46 compressor oil — 0.25 qt

Preparation

1. Park vehicle on level surface and turn off engine
2. Allow engine to cool if recently operated
3. Verify AC system has been properly recovered using approved refrigerant recovery equipment
4. Confirm system is at atmospheric pressure using manifold gauges
5. Have new PAG 46 oil container sealed until ready to use

Procedure

1. 1

   Locate AC service ports
   Open the hood and locate the AC system service ports. The low-side service port is on the suction line (larger diameter line) running from the evaporator outlet to the compressor. The high-side port is on the discharge line near the compressor. The compressor is mounted on the driver side of the engine block, low and forward.
2. 2

   Verify system evacuation
   Connect manifold gauge set to both high and low side service ports. Verify both gauges read zero or atmospheric pressure. If system shows pressure, it must be properly recovered before proceeding. Do not proceed if refrigerant is still present in the system.
3. 3

   Determine oil quantity needed
   If adding oil due to component replacement, measure the oil drained from the removed component and add the same amount to the system. For routine service top-up, add 2 ounces of PAG 46 oil. For complete system flush or new compressor installation, refer to the factory-specified total oil capacity for this vehicle and subtract oil already present in other components.
4. 4

   Prepare PAG oil injector
   Fill the PAG oil injector tool with the measured quantity of fresh PAG 46 oil. Work quickly to minimize moisture absorption. Ensure the injector is clean and free of contaminants. Most injectors have measurement markings in ounces or milliliters for accurate dispensing.
5. 5

   Inject oil through low-side port
   Remove the low-side service port cap. Attach the PAG oil injector to the low-side service port. Slowly inject the measured oil quantity into the system through the low-side port. The oil will be drawn toward the compressor suction and distributed through the system during operation.
6. 6

   Disconnect injector and secure port
   Once all oil has been injected, disconnect the PAG oil injector from the low-side port. Immediately reinstall the service port cap to prevent moisture entry and contamination.
7. 7

   Rotate compressor clutch
   Manually rotate the compressor clutch hub 10-15 revolutions to distribute the oil internally through the compressor. This prevents hydraulic lock when the system is recharged and started. Access the clutch from underneath or through the wheel well on the driver side.
8. 8

   Evacuate system
   Connect the AC recovery/recharge machine to both service ports. Evacuate the system to proper vacuum (29 inches Hg minimum) and hold for at least 30 minutes to remove air and moisture. This step is critical after opening the system to atmosphere.
9. 9

   Recharge AC system
   After successful evacuation and vacuum hold test, recharge the system with the specified amount of R-134a refrigerant according to the underhood AC specification label. Recharge to the exact R-134a capacity listed on the underhood AC specification label for this specific vehicle (verify against factory service data before charging).

Reassembly

1. Ensure all service port caps are securely installed
2. Verify no tools or equipment are left in engine bay
3. Close hood after confirming all connections are secure

Verification

• Start engine and turn AC to maximum cold setting with fan on high
• Allow system to run for 5 minutes and verify compressor clutch engages
• Check for proper cooling from cabin vents (vent temperature should reach 40-45°F)
• Inspect all AC line connections for signs of oil leakage
• Use manifold gauges to verify system pressures are within normal operating range (low side 25-35 PSI, high side 200-250 PSI at idle with ambient temperature 70-80°F)
• Listen for abnormal compressor noise that might indicate overfill or insufficient oil

Related trouble codes on this vehicle

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