There are five families of aluminum pumps currently available: Group 0.5, 1, 2, 3 and 4, some can be combined to make multiple pumps.

 All Turolla OCG gear pumps use hydrodynamic journal bearings that have an oil film maintained between the gear/shaft and bearing surfaces at all times. If this oil film is sufficiently sustained through proper system maintenance and operating within recommended limits a long pump life can be expected.