Chris ... 12/18/2016
2003 Mercury Grand Marquis GS 8 Cyl 4.60L
occassional jolting sensation when driving
About once a week while driving on cold mornings 40-50 mph there is a sudden jolt felt in the seat, then car seems normal and doesn't do it again. Didn't do it last winter.
Several possibilities; low transmission fluid level, transmission hesitates when shifting, engine slight misfiring - to name only a few.