Characteristics of a Driveshaft Assembly

Double Cardan Joint

Ball Stud Yoke

  • Welded to the driveshaft, providing a direct connection between the driveshaft and the U-joint.

  • The inner section of the yoke is a stud that fits into the centering ball.

  • This connection mechanically links the ball stud yoke and the flange yoke, allowing proper articulation and torque transfer in the driveline.

  • Supports smooth rotation while accommodating angular changes in the driveshaft.

Ball Socket Yoke

  • Connects the ball stud yoke and flange yoke, acting as a pivot point.

  • Allows the driveshaft to transfer motion smoothly between sections while accommodating angular changes.

  • When the front section of the driveshaft moves, it causes the opposite section to move in the opposite direction, maintaining consistent power transfer and reducing vibration.

Centering Ball Spring

  • Presses firmly against the ball located between the two driveshafts.

  • Holds the ball securely in the socket, maintaining proper tension.

  • Prevents the centering ball from moving back and forth, which would otherwise cause clunking noises in the driveshaft.

  • Ensures smooth operation and consistent power transfer between the connected driveshaft sections.

Coupling Yoke

  • Acts as a carrier connecting and holding two simple U-joints together.

  • Enables the driveshaft to operate at greater angles than a single U-joint could handle.

  • Helps prevent vibrations when the suspension moves over variable road surfaces.

  • Supports smooth power transfer while accommodating driveline angular changes.

Two U-joints

  • Two U-joints work together to transmit power through the driveshaft.

  • The U-joints hold the yokes steady while allowing them to flex relative to each other.

  • This design smoothly transfers power to the driving wheels.

  • Helps minimize vibration, even at higher operating angles.

Flange Yoke

  • Connects the second U-joint to the rear axle pinion or another section of the driveshaft.

  • May hold the centering ball and spring, ensuring proper alignment and tension.

  • Typically includes a grease fitting to allow lubrication of the centering ball.

  • The attachment method to the pinion flange can vary depending on the application (e.g., bolts, U-bolts, or straps).

Types of Driveshaft Tubes

One-piece Driveshaft Tube

  • Extends uninterrupted from the transmission to the differential.

  • Can be made from steel, aluminum, or composite materials.

  • Rotates at high speeds, which can create vibration and noise.

  • Balance weights are attached to reduce vibration and ensure smooth operation.

  • U-joints connect each end of the driveshaft, allowing power transfer while accommodating chassis movement over rough terrain.

  • A slip yoke allows the driveshaft to slide in and out, compensating for changes in distance between the transmission and the drive axle during suspension travel.

Two-piece Driveshaft Tube

  • The two-piece driveshaft consists of two driveshafts connected in the center with bearings and sometimes a constant velocity (CV) joint.

  • This design is used when the distance between the transmission and drive axle is too long for a single driveshaft.

  • A U-joint is typically installed at each end of the driveshaft to accommodate vehicle movement.

  • A slip yoke allows the driveshaft to move in and out, adjusting for changes in distance between the transmission and drive axle.

  • Often, a two-piece driveshaft has two slip yokes—one at the transmission and one at the center support bearing—to manage the changing relative distance between all three components during travel.