233 / 274
16-6
U.S. 888-725-9355
Canada 800-387-3889
DRIVELINE TIPS III
ANGLES AND VIBRATIONS
1. Driveline vibrations can occur as five various types, transverse, torsional, inertial
excitation, critical speed, and secondary coupling vibrations.
2. Transverse vibrations are simplest to repair and usually involve balance issues on
driveshaft.
3. Torsional vibrations are more serious vibration issues that are usually related to driveline working
angles, and bending and twisting motion experienced by driveshaft.
4. Large working angles will usually introduce torsional vibrations. Keeping driveline slope
3° to 6° is preferred. The smaller the angles, the less chance of torsionals.
5. Cancellation angles is the process where you keep the front and rear working angles to
a + / - 1° of each other. Keeping angles small and + / -1° of each other will help cancel out torsionals.
6. Ride height will affect angles and relate to vibration issues. When checking into a vibration issue the
truck should be loaded.
7. There are two types of angles to be aware of simple 1 plane angles and compound
angles.
8. Simple 1 plane angles are where the driveshaft connects to the rear axle and is in a straight line
plane.
9. Compound angle is where the driveshaft is offset in relation to the transmission and rear axle, not in
a straight line plane.
10. Driveline slop is the direction, up, or down, of the driveshaft and the slope should not
exceed 3° to 6° to avoid torsional vibrations.