Mr. Ralph Topper

[Ralph Topper]

I bought a new 2019 3500 GMC Denali Dually Diesel VIN: 1GT42WEY1KF222186  in May2019, the day I picked it up I drove it onto the PA Turnpike and went up to speed and there was a definite vibration especially at 65-75 mph. I took it to the dealer and had all the tires balanced at least 3 times and I still have a vibration coming from the rear of the truck. I took it to the dealer in November and they put the PECO reader on it but said they couldn't duplicate what I feel, this thing is smooth as glass up to 60mph and then it starts. This is not a massive vibration but definitely is irritating. I had a 2007 Chevrolet 3500 SRW and it had the same symptoms later on after the warranty, I took it to a driveshaft guy who balanced the driveshaft and it was perfect at all speeds after that. I need to know what GM says the next step should be, the truck has 24K miles on it and I want it be fixed, it has gone on long enough,