A forward carrier assembly for a tandem axle vehicle, comprising:
- an inter-axle differential (IAD), the IAD comprising an IAD housing having an internal spline;
- a differential spider comprising a plurality of legs attached to the IAD housing and a plurality of spider gears mounted on. the legs;
- a first side gear engaged with the spider gears on a first side of the spider, the first side gear having an internal spline;
- a second side gear engaged with the spider gears on a second side of the spider;
- and
- a collar having one more external splines, the collar being movable between a first position in which the one or more external splines engage with the internal spline of the IAD housing and the internal spline of the first side gear, and a second position in which the one or more external splines is disengaged from the internal spline of the LAD housing and engaged with the internal spline of the first side gear.