An exchangeable spindle assembly for a machine tool. The spindle assembly includes an assembly attachment coupling being connectable to said machine tool, a tool spindle having a predetermined spindle diameter, and a spindle drive coupling being connectable with a drive mechanism of the machine tool. The drive coupling communicates with the tool spindle whereby rotation of the drive coupling effects rotation of the tool spindle. The spindle assembly further includes at least one coolant distribution manifold being connectable with a coolant supply source on the machine tool via a coolant connection on the spindle assembly. The spindle assembly being arranged in a manner whereby upon mounting the spindle assembly on the machine tool, the assembly attachment coupling, spindle drive coupling and coolant connection are all concurrently connectable to the machine tool. Additional connections may be included.