Could be a few things. First check your Transmission Fluid if it is low, if so fill it to the fill line. Second check the transmission oils to see if it is dirty; if so have it completely drained and replace transmission filter, and tranmission oil. Approximatly takes 4.2 quarts to refill completely. If problem still persists then most likely the transmissions torque converter is going bad, or there could be a leak in the transmission cooling line, either in the pressure line or the return line. Sometimes the leak may not be detected but can cause a vapor leak and cause the tranny to switch gears hard. Lastly check the vacuum lines to the tranny or if it calls vacuum lines for the peticullar year.
You may have a worn or broken universal joint.
check the u-joints
Typically when an automatic transmission runs out of fluid, you will notice an increase in RPM's between shifts as well as the shifting nor being as smooth (clunks into gear). When the fluid gets extremely low, the car will simply cease to move as there isn't enough fluid to build pressure to allow the transmission to work properly. At this point, you've likely caused internal damage and fixing a leak/adding more fluid will not help.
Sounds like a warped brake rotor(s).
Growl, whine, clunks,
check your vacuum lines on the top left area of the engine. mine slipped off and it resulted in clunking and poor engine performance. put it back on and problem was solved.
i'm getting this checked out today with my mechanic also.
You are saying that on a smooth flat road driving in a straight line you are hearing a clunking sound? Is that coming from the front or back? Does the clunk happen just once or is there a frequency? If it happens more than once, does it change with vehicle speed?
usually if it clunks on clutch release its the a frame ball joint on the rear axle
Can you be a little more specific? Like where the clunk is coming from, and/or what you're doing when it clunks? FriPilot
Strut bushing wore if it doesn't do it on a smooth road. Clunks on a rough road only. Fixed mine
Control arm bushings.