Hello! I drive a 2007 3.6 L V6 automatic Cadillac CTS with 170,000 miles on it, I have been having a problem where Most of the time when I shift from reverse to drive or a park to drive, my car will feel like it is slamming into drive. It is so aggressive that it actually jolts the entire car slightly forward. However it sounds like it might be coming from the back. I have asked a good amount of friends and mechanics but no one seems to know. Is there a way to fix this or any idea of what it might be?
https://www.youtube.com/watch?v=w_d7aD9jDg8
It got to be the automatic transmission. If that bad you need to have someone with a dealer level scan tool like Scotty scan and see what going on with it. It could also be something like a misfire but because it only happens when you shift that's gotta be the culprit. If it is the transmission is going out try and see if you can find a used one from a junkyard. Its going to a LOT cheaper than buying a new one if you even can anymore and barely anyone knows how to rebuild transmissions properly so don't get it rebuilt.
Did you also the check engine and transmission mounts?