US Patent 7837588 Pre-load mechanism for helical gear differential

A differential assembly for a vehicle includes a differential casing rotatable about an axis. The differential casing defines a cavity. A pair of side gears is disposed within the differential casing cavity. First and second pairs of pinion gears are rotatably positioned in the cavity in driving engagement with the side gears. A thrust block has circumferentially spaced apart recesses. Rotation of the thrust block is restricted by the first and second pairs of pinion gears being in communication with the recesses. A spring biases the thrust block into engagement with one of the side gears.