I bought my 20015 Colorado used with 26,000 miles my son in law checked the VIN it has not had any of the update calibrations done. I am hoping it fixes the transmission shifting and the flat spot on the gas pedal. I am still getting a Pedal Commander. I have been driving in tow mode but I am looking for a better solution. My truck is bipolar at times it drives good not hardly any lag on the gas pedal and other times it lugs and you have to step on hard to get the transmission to shift down so it will get out of its own way. My son in law is a Chevrolet tech he is going to see what he can do with it.
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