A piston assembly having a piston member and a connecting rod. The piston member has a crown portion and a lower portion bonded together with a cooling gallery formed between them. The connecting rod has a ball end which is positioned in a socket in the piston member. In one embodiment, the ball end can have two flat surfaces and be held in position by C-clips. In another embodiment, the ball end is cylindrically shaped and the socket has a corresponding shape.