Leading wheel
（重定向自Leading axle）
![The leading wheels (boxed) on a 4-6-2 locomotive](/Images/godic/202501/23/462leading_flip4405.jpg")
The leading wheel or leading axle or pilot wheel of a steam locomotive is an unpowered wheel or axle located in front of the driving wheels. The axle or axles of the leading wheels are normally located on a leading truck. Leading wheels are used to help the locomotive negotiate curves and to support the front portion of the boiler.