Definition:
A type of hub used on the front axle of some 4-wd vehicles which has a mechanism that can turned to lock the hub to the axle for 4-wd use. The unlocked position allows freewheeling for times when 4-wd is not needed.
Related Terms
• Hub
Related Resources:
How and When to Operate Your Four Wheel Drive
Learn when and how to use your truck's four wheel drive (4-wd) system.

