The problem occurs all the time between 32 and 40 mph. Particularly noticeable on freshly paved roads. Just replaced right front axle, fixed heat shield on exhaust and replaced disc pads on front brakes and resurfaced rotors. Tires realigned and balanced. Mechanic thought new axle was defective and put in another one. Same noise/vibration exists. It only occurs when accelerating--doesn't happen in neutral or coasting downhill.