The vehicle shakes or vibrates when accelerating in low gears. It typically occurs when the vehicle shifts between the 1st and 2nd gears on automatic transmission. The whole car shakes. The only way to stop it is by removing foot from gas pedal or accelerating car quickly to higher speed. The issue affects the ability to safely accelerate to proper speed. Begins when accelerating from a stopped position all the way up until car reaches about 30-40 miles per hour.