Driveline System: Notes

WARNING: This page is about a different car, the 2013 Ford F-550 Super Duty, 2013 Ford F-450 Super Duty, 2013 Ford F-350 Super Duty, and 2013 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.

The source of the drivetrain power is generated by the engine and delivered to the transmission. The driveline transfers the engine torque through the driveshaft to the axle.

On 2-Wheel Drive (2WD) vehicles, power is transmitted through the transmission to the driveshaft and then to the rear axle.
On Four-Wheel Drive (4WD) vehicles, power is transmitted through the transmission and the transfer case. The transfer case directs the power to the rear driveshaft and then to the rear axle. When engaged, it also transmits power through the front driveshaft to the front axle.

There are 4 types of driveshafts used:

One-piece rear driveshaft with 2 U-joints and a front slip yoke.
Two-piece rear driveshaft with 3 U-joints, a front coupling shaft, a center bearing and a rear slip yoke.
Three-piece rear driveshaft with 4 U-joints, 2 center bearings and a rear slip yoke.
One-piece front driveshaft with a single U-joint, a double cardan U-joint and a slip yoke.

The rear driveshaft is connected to the output shaft of the transmission or transfer case and to the rear axle. The front driveshaft is connected to the transfer case and to the front axle. U-joints are used at both ends of the driveshaft to allow for angular motions. Slip yokes are used to allow for any changes to the length of the driveshaft. The engine torque enters the axle through the drive pinion, which rotates the ring gear. The ring gear is mounted to the differential case, which contains the gears that transmit power to the rear axle shafts or front halfshafts. These shafts rotate the drive wheels.