Ok, I just bought this truck used from a Mitsubishi-Hyundai Dealership. It's a 2007 Chevrolet Silverado 1500 Ext. Cab Classic with a 4.3 Vortec, Code X and with only 17K miles on the truck. My problem is that the exhaust will make some strange vibration when I accelerate to 1200-1400 RPM. It sounds like a growling bear or somekind of noise, but diminishes when accelerated to higher RPM. But anyway my truck is still under factory warranty. Does anyone ever had this problem before?
