US Patent 11698123 Axle assembly having an interaxle differential unit

An axle assembly having an interaxle differential unit. The interaxle differential unit includes first and second side gears and a gear nest but does not have a case. The gear nest includes a spider having at least one spider shaft, a pinion gear that is rotatably disposed on the spider shaft, and a pinion gear retainer that is fastened to the spider shaft to retain the pinion gear.