Driveshaft Phasing Description
The driveshaft is designed and built with the yoke lugs (ears) in line with each other. This produces the smoothest running shaft possible. A driveshaft designed with built in yoke lugs in line is known as in-phase. An out of phase driveshaft often causes vibration. The driveshaft generates vibration from speeding up and slowing down each time the universal joint goes around. The vibration is the same as a person snapping a rope and watching the wave reaction flow to the end. An in phase driveshaft is similar to 2 persons snapping a rope at the same time and watching the waves meet and cancel each other out. A total cancellation of vibration produces a smooth flow of power in the drive line. All splined shaft slip yokes are keyed in order to ensure proper phasing.