heh, i didnt type insim....that wuz problem.
but i got that effect in custom camera too not only in car! but my custom camera is positioned slightly different than original in car cam, maybe that's why. hmmm
If that's the setting I think it is, I knocked that down to 0. When patch Y came out and it was defaulted to (any number), I was amazed and confused at how the view suddenly became ultra-UNrealistic. In no way are your eyeballs shaking like that. Your point of view is stationary when hitting bumps and the objects around you (car cockpit) will move and shake within your peripheral view. What your view is focused on would not be shaking and moving around.
Look out a window and focus on a tree or something outside in the distance. Now shake and move your head around while focused on the tree. Notice the tree doesn't bounce and shake all around. Notice the windowframe in your peripheral vision (just notice it peripherally, not focused on it.) You see the window shaking and bouncing in relation to the stationary view of the tree. That is realistic, not the tree that you are focused on bouncing and shaking.
Do the opposite, focus on the window frame. Now the tree in your peripheral vision will be moving around as you shake and move your head while the window frame will be stationary.