Q: I have a 2011 Chevy Colorado V-8, 4WD extended-cab with 5700 miles. At approximately 5500 miles, the transmission started making a clicking sound during shifting. It's most pronounced between second and third gear on upshift, and downshift is not as loud. Chevy service changed the valve body and sensors, but after 100 miles, the noise is back.

A: I'm not aware of a problem where the valve body (containing control solenoids) will produce a notable clicking noise while shifting. Each computer-controlled solenoid simply opens and closes a path for hydraulic fluid to apply and release internal components, such as a clutch, lock-up torque converter, etc. Every solenoid does make a clicking noise, but nothing that would be heard over normal engine noise. You're still well within the powertrain warranty, so get the truck back to Chevy service for diagnosis.

A lot of 4x4 drivetrains will produce a notable "clunk" noise that's considered normal. This is because of needed clearances between parts in the transmission, transfer case, and the rear and front axles. GM does have a TSB that describes this condition as occurring with the 2-3 upshift and 3-2 downshift. The Chevy techs should be able to provide you with some information following a test drive, as long as they are able to duplicate the noise. If it's because of normal drivetrain slack, they can put you in a similar truck to prove the point. If the techs determine the noise to be abnormal, it's their job to continue diagnosis and find a fix.


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