Do transmissions make humming almost vibrating sounds when they go bad? There is a sound coming from underneath my shifter at low speeds and idle. When I accelerate it stops. I used to have a knocking sound in the same spot but that turned out to be part of my exhaust being upside down and hitting the body. I think the shop said it was a clamp. I'm wondering if the clamp is possibly rotating or if my tranny is going bad. It does it when driving at any speed but it vibrates less at higher speeds. Odd sound - YouTube