Have a 2004 duramax 2500 4x4 crew cab. Recently bought the truck and have noticed a vibration from the drivetrain between 100 and 120 km/h. Truck runs perfect at any other speed.
It has a 2" lift, with 33" tires which are not too agressive.
Interesting thing is the vibration only happens when under acceleration.. no shaking in steering wheel. Previous owner says vibration only started when tires were changed, but I cant see tires having anything to do with it as it doesn't vibrate at these speeds unless under acceleration/power while climbing. Any ideas where to start? drive shaft, u joint? Could it really be tires? thanks!