Vibration During Slow Acceleration
07 Nissan Altima 2.5SL
When I'm accelerating slowly, from around 40km-65km, my car begins to vibrate. Even the passenger can feel it. It feels as if something in the front end (engine area) is vibrating. My acceleration pedal also begins to vibrate. It happens mostly during school zones, or low speed areas. If I accelerate quickly, then the vibration doesn't happen, which I mostly do so I can avoid it. It's fine on highways or high speed areas, it's just when I'm going slowly.
I took it to the dealership and the guy said that's normal. It's trying to shift gears but unable to do so because I'm accelerating slow (or something).
Is that true? Or is there a problem? Does anyone know the real reason as to why it's vibrating?