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Makes 🢒 Cadillac 🢒 2004 🢒 Escalade EXT 🢒 Bulletins 🢒 Diagnostic Information for Moan, Groan or Boom Noise at Idle, Vibration in Steering Wheel or Felt through Floor when A/C Compressor Engages - Do Not Replace A/C Compressor

Diagnostic Information for Moan, Groan or Boom Noise at Idle, Vibration in Steering Wheel or Felt through Floor when A/C Compressor Engages - Do Not Replace A/C Compressor

Subject:Diagnostic Information for Moan, Groan or Boom Noise at Idle, Vibration in Steering Wheel or Felt Through Floor When A/C Compressor Engages -- Do Not Replace A/C Compressor

Models:2003-2005 Cadillac Escalade, Escalade ESV, Escalade EXT
2003-2005 Chevrolet Avalanche, Suburban, Tahoe
2003-2005 GMC Yukon, Yukon XL
2003-2005 HUMMER H2
with Air Conditioning (RPOs CJ2, CJ3)


As a result of the compressor parts restriction program, a number of A/C compressors are being replaced due to a noise concern. A failed parts analysis found that the compressors were "No Trouble Found".

Noise concerns may be a moan, groan, or boom noise while the vehicle is idling or a vibration that is felt in the steering wheel and/or through the floor. These conditions are most noticeable when the air conditioning (A/C) compressor engages and may be caused by a vehicle vibration and/or noise that resonates through the exhaust system and is load sensitive.

Technicians are to refer to the service information listed below to verify and fix the customer concern:

    • Raise the engine idle speed from just off of idle to 2000 RPM. If a resonance or moan is noticed, refer to PIP3121B for repair procedures.
    • If the vibration and/or moan is noticed at idle, refer to PIT3203 for more information.
    • Inspect the engine mounts for a ground out condition. Refer to Corporate Bulletin Number 04-06-01-023 for repair procedures.
    • Inspect the exhaust heat shield for separation from the muffler. If a concern is noticed, refer to Corporate Bulletin Number 03-06-05-008A for repair procedures. Please note that this Service Bulletin does not apply to all vehicles. It only applies to the specific models listed in the bulletin.
    • Refer to Corporate Bulletin Number 01-01-38-013A for more diagnostic information to consider before replacing the A/C compressor.

If the customer concern is not corrected after all the repair procedures listed above have been performed, technicians are to contact TAC for more information. Replacing the A/C compressor will not correct the customer concern. Please have a list of repairs performed and documents used before talking to the TAC consultant.