5L40E , Transmission Driveline Exhaust Growl Moan 35-45 MPH 5th Gear TCC - kw 3.2 axle automatic fifth LA3 shudder vibration

When servicing the vehicle with the VIN you entered, the following diagnosis might be helpful if the vehicle exhibits the described symptoms.

Customers and dealer personnel may notice that the 2003-2004 Cadillac CTS (DB) equipped with the 5L40E automatic transmission produces a driveline/exhaust growl/moan noise at speeds of approximately 35-45 MPH (56-72 km/h) in 5th gear with the TCC applied. The noise can be produced by driving approximately 35-45 MPH in 5th gear with TCC applied and lightly increasing throttle just enough to maintain a constant speed but not enough to force a downshift to 4th gear or to release TCC.

The condition has been determined to be characteristic. The vehicle should be compared to an identical vehicle for comparison.

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Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed. If these steps do not resolve the condition, please contact GM TAC for further diagnostic assistance. This diagnostic approach was developed for the vehicle with the VIN you entered and should not be automatically be used for other vehicles with similar symptoms.

(03, 04 Cadillac CTS)

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