Just got a 2005 TL AT with about 56K miles on it. I have a question for you guys. Is it normal for the car to downshift when the car is slowing down to the point where you can feel it downshifting? Right at about 40mph I feel the car jerk into what I am assuming is either 3rd or maybe even 2nd gear. The owner's manual says the car will downshift to help slow the car down, but I swear my head whips forward sometimes when it downshifts. Anyone else experience this? I got the transmission fluid changed as I thought that might clear it up, but that didn't do anything. Is it normal to feel the car downshift when applying the brake or slowing down? Thanks for your input. I appreciate it.

 

Yup. A search will provide all the info you need:
https://acurazine.com/forums/3g-tl-2004-2008-93/car-slows-down-itself-569598/
https://acurazine.com/forums/3g-tl-2004-2008-93/difficulty-coasting-548549/

Just remember the 3G garage for info.