Car shaking when accelerating?

Being that car has a CVT transmission with a less than stellar reputation I suspect it is the item at fault. The CVT is basically 2 pulleys with a metal "belt" between them. It alters the drive ratio by having that belt slip up and down between the two pulleys. Any jolt is either a scored area on one of the pulleys or more commonly the shafts that the two pulleys slide on starts to fail and the sheaves no longer slide properly. Usually it doesn't even set a code, it just starts showing the mechanical signs of failure. As a result Nissan extended the warranty on those vehicles from the original 5yr 60K out to 7yrs and 84K. So the first thing I would do is talk to your local dealer and see if they will work with you on a replacement, even though you are over on the mileage. Perhaps call Nissans customer service directly and talk to them about it as well. 1 (800) 647-7261 Nothing like going into the dealership with a prior authorization to have the work done. CVTs are incredibly touchy units and the JATCO units in those vehicles seem to be failure prone. Plus unfortunately there isn't much that can be done on them without having a dealer level scan tool to test it with while in operation. About the only thing that can be done is to check the fluid levels, but unless the transmission is leaking it's doubtful that it's low. Checking it requires that you get the vehicle elevated in a level and secure manner, then you remove the plug from the transmission and install the charge adapter (KV311039S0) and then with the engine running at an idle you add fluid. Then remove the adapter and let any excess fluid run out until it stops dripping. Then install the plug.