Rumbling / shaking during certain types of accelleration
I just bought a used 2014 Compass latitude 2.4L / 6-speed a couple weeks ago. I've noticed that about 10-20% of the time there will be a rumbling vibration which seems to come from the engine compartment, only while accelerating moderately. Very light or very hard acceleration rarely produces it, but it sometimes does.
It seems to happen more often when accelerating moderately from a slower speed, like if Granny Smith just turned off the road going 15mph, or accelerating out of a slow turn, like turning right/left out of a parking lot from a light.
Changed the spark plugs with new OEM from Mopar and a Fram air filter because I wanted to, anyway. No improvement.
May need to take it back for the dealer's 6 mo / 6,000 mile warranty...