Transmission or a belt?

2012 GMC SIERRA
24,905 MILES
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THISGUY2120
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I have a 2012 GMC Sierra 4.3L V6 automatic transmission and the problem I have is a pronounced buzzing/humming noise when I accelerate in 2nd and 3rd gear. The sound seems to happen more often when its around 1500 RPM or keeping a steady speed around 20-40 MPH. The question is could that be a transmision problem or one of my belts going bad?

Apr 17, 2013 at 11:53 AM
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HMAC300
  • ✓ASE Certified Mechanic
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  • ASE Certified Mechanic
spray water on your belt if sound goes away replace belt and tensioner
Apr 17, 2013 at 12:08 PM
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