The initial Clown Car from ss13, was not designed with the physics of ss14 in mind, where it is a lot easier to "clip" the edge of a wall or table, and immediately spill its contents. I would suggest giving it a "HP", that slowly regenerates, losing 1 every time it hits an object. Only if it reaches 0 does it spill.
Also make it inheret accesses of people in it because thats hella funny.