Axle Noise - Clunk

AXLE NOISE - CLUNK
Clunk is a metallic noise heard when the automatic transmission is engaged in REVERSE or DRIVE. The noise may also occur when throttle is applied or released. It is caused by backlash somewhere in the driveline or loose suspension components; it is felt or heard in the axle.
Additionally, clunk may be heard upon initial drive-away. This occurs as engine torque shifts vehicle weight, forcing changes in driveline angles, preventing the propeller shaft slip-yoke from sliding on the output shaft. To correct for this condition, lubricate the slip-yoke splines.