Tech Article - CV Boot Insection
The driveaxle boots are really important because they prevent dirt, water and foreign material from getting into the inner axle joints early models or Constant Velocity CV joints 1968 and later automatic stick shift and 1969 and later manual transaxles.
Raise the vehicle and support it securely on jackstands.

Look over the boots for tears, cracks and loose clamps. If you see anything, they must be replaced.

Constant Velocity CV joint check later models.
The most common symptom of driveaxle or CV joint failure is knocking or clicking noises coming for the affected area while the vehicle is moving.

Take each axle and rotate it in both directions while holding the CV joint housings to check for excessive movement, indicating worn splines or loose CV joints.

Look over the mounting bolts for looseness. Tighten the bolts to the torque.

Replace any joints that are bad.