So you're driving down the road, and you hear a snap or perhaps a pop. Maybe you took a corner a little hard, and you noticed a squealing or squeaking sound coming from one of your front wheels. All of these and more are signs that your ball joints are losing their grease and starting to fail. The last thing you want from your steering and suspension systems is an ungreased ball joint that's become dry and stiff. It could lead to a dramatic decrease in steering responsiveness, which is more than just an inconvenience - it's a hazard. If your ball joints cannot effectively adjust the wheel's steering angle, then you could end up with two front wheels pointing in different directions. At best, this could result in uneven wear on your tires and a very loud whistling sound as you drive. At worst, your car can become unsteerable leading to a potential collision or just plain inoperable. That's not good for anyone, so replace your ball joints if they are showing signs of early failure.
A great deal of modern technology is comprised of inventions that were inspired by nature. Velcro was famously inspired by the microscopic view of the burrs of a burdock plant. Automotive ball joints are essentially mechanical versions of the anatomical ball and socket type joint found where your hip meets your pelvic bone. And just like your hip joint, a ball joint allows a limited range of motion in all directions on two planes. When added to control arms and tie rod ends, a ball joint is the perfect fit for steering and suspension applications, which is why ball joints can be found on virtually all vehicles built today. Prior to the control arm and ball joint design in today's suspensions, kingpin sets were used at the end of a beam axle in the front of a car. This allowed for adequate control over steering angle, but did not make any room for vertical movement without adjusting the whole vehicle's geometry.
If you think your ball joints are going bad, then it would be wise to check them and/or replace them if necessary. This doesn't have to be a monumental task, and as long as you or your mechanic have the proper tools and experience replacing ball joints can take only a few hours.