I have a propeller type noise when i engage the gas and decrease from the pedal. on 2006 Chevrolet Avalanche 1500

Someone told me it is my transfer case. I have around 190k miles on it ... just recently had a new tranny put in. sounds like a propeller winding up when i hit the gas and increase speed. when i take my foot off the gas it winds down. HELP

seek insp and diag