A mining shovel includes a boom and a transmission unit coupled to the boom. The transmission unit includes an outer housing, an internal motor housing disposed within the outer housing, and a venting system coupled to the outer housing to direct air through both the outer housing and the internal motor housing.

A ground engaging tool locking system includes a pin having a first, proximal head region and a second, distal end region spaced from the first, proximal head region along an axis. The pin includes a groove located between the first, proximal head region and the second, distal end region. A biasing element is disposed at least partially within the groove.

A mining shovel includes a boom and a transmission unit coupled to the boom. The transmission unit includes an outer housing, an internal motor housing disposed within the outer housing, and a venting system coupled to the outer housing to direct air through both the outer housing and the internal motor housing.

A mining shovel includes a boom and a transmission unit coupled to the boom. The transmission unit includes an outer housing, an internal motor housing disposed within the outer housing, and a venting system coupled to the outer housing to direct air through both the outer housing and the internal motor housing.