Drive axle assembly with lubricant cooling system

A drive axle assembly having a gear housing and axle tubes extending outwardly of the gear housing, a lubricant reservoir in the gear housing, a rotatable member forming part of a gear assembly rotatably mounted in the gear housing, the rotatable member being partially disposed in a lubricant in the lubricant reservoir and partially disposed above the lubricant in the lubricant reservoir, and a lubricant cooling system, the lubricant cooling system comprising:

• a lubricant passage formed by a cover and an insert that are attached to the gear housing, the lubricant passage being in fluid communication with the lubricant reservoir via an inlet formed in the insert that is exposed to the lubricant in the lubricant reservoir,
• the inlet being disposed with respect to the rotatable member so that the lubricant passage is filled with a part of the lubricant to a level higher than the level of the lubricant remaining in the lubricant reservoir when the rotatable member rotates,
• the lubricant passage having outlets formed in the insert above the inlet for delivering the part of the lubricant from the lubricant passage when the part of the lubricant in the lubricant passage rises above a predetermined level, and
• lubricant ducts disposed in the respective axle tubes that have inlets in fluid communication with the outlets of the lubricant passage and outlets disposed outboard of the inlets that are in fluid communication with the axle tubes for returning the part of the lubricant from the lubricant ducts to the reservoir along the interior of the axle tubes.

A drive axle assembly having a gear housing and axle tubes extending outwardly of the gear housing, a lubricant reservoir in the gear housing, a rotatable member forming part of a gear assembly rotatably mounted in the gear housing, the rotatable member being partially disposed in a lubricant in the lubricant reservoir and partially disposed above the lubricant in the lubricant reservoir, and a lubricant cooling system, the lubricant cooling system comprising:

• a lubricant passage in fluid communication with the lubricant reservoir via an inlet that is exposed to the lubricant in the lubricant reservoir,
• the inlet being disposed with respect to the rotatable member so that the lubricant passage is filled with a part of the lubricant to a level higher than the level of lubricant in the lubricant reservoir when the rotatable member rotates,
• the lubricant passage having an outlet disposed above the inlet for delivering the part of the lubricant from the lubricant passage when the part of the lubricant in the lubricant passage rises above a predetermined level, and
• lubricant ducts disposed in the respective axle tubes that have inlets in fluid communication with the outlets of the lubricant passage and outlets disposed outboard of the inlets that are in fluid communication with the axle tubes for returning the part of the lubricant from the lubricant ducts to the reservoir along the interior of the axle tubes,
• the lubricant ducts being formed by inner and outer elongated parts that are secured together.