Different Transmisson noise????

[petersami]

so i know many of you are getting a rattling noise but i've been getting something different. when ever my car has been sitting for a while and i take off i've been getting a 1 count them 1 knocking noise. when i back up (up hill is a LOT worse) i can feel it a lot more. its usually within the first 10 feet or so but sometimes its a quite little thud i have to listen for... and other times i feel like i backed into someting.

like i said it only happens when the car has been sitting for a few hours and then it drives completely normal. after reading that a lot people are having transmission issues i feel a bit better. thanks for any helppete

[Ticmxman]

Sounds a lot like the anti-lock brakes doing the normal self-check.

[philipa_240sx]

+1 for the ABS self check. I sometimes hear buzz or thud when first backing up or moving forward. My Altima made similar noises.

[petersami]

that could be it... but the only problem is is that i dont recall hearing it when i first bought the car.... but that does make sense, except it only happens after the car has been sitting for a few hours.