Over time the rubber boots of the CV joints can become cracked, torn, or otherwise compromised. Once moisture and dirt get into a CV joint and grease makes its way out, the CV joints days are numbered. Signs of impending failures are a click-click-clicking or metallic crackling noise while turning and accelerating or a clunking upon deceleration. While one can repack, reboot, and rebuild CV axles, it makes more sense for the average do-it-yourselfer to procure replacement units and swap out the old axles. If a boot is torn or missing, it is possible to save the joint if caught early enough, but usually the damage has already been done. Replacing or servicing the entire CV joint axle assembly may be the smarter move since replacing a boot may involve removing an axle, which may also involve removing half or all of the vehicle's brakes and suspension.