Lift axles are non-power axles and are used in most commercial vehicles in order to increase their load bearing capacity. These axles are movables axles (up or down) i.e. can be lifted up or deployed as per the load on the vehicle or the road condition. Lift axle contributes to improve fuel economy and reduces maintenance and tyre wear.

Lift axle can be mounted in-front or behind the drive axle. The lift axle which is mounted in-front of the driving axle is called "Pusher type lift axle" and the lift axle which is mounted behind the driving axle is called "Tag type lift axle".