A reciprocating pump assembly includes a power frame that houses a crankshaft. The crankshaft is mechanically connected to a large gear or bull gear on each end that is in mechanical engagement with a small gear or pinion bearing. A bearing housing is integrally formed as part of the power frame with an increased width and a constant inner diameter. A pinion bearing assembly, having an inner race, an outer race, and spherical bearings is placed around the shaft of the pinion bearing. The pinion is installed in the reciprocating pump assembly such that the bearing assembly rests on the bearing housing, which is integrally formed as part of the power frame. The bearing assembly is free to float in the bearing housing and provides for some lateral movement of the shaft and bearing assembly during operation of the reciprocating pump assembly.