The steering linkage on your car is composed of a group of movable rods and arms, connected by ball joints. These joints work a lot like the joints of your hips, but unlike hip joints they need periodic lubrication. You can readily do this lube job yourself.

How often should you lubricate ball joints? I do it with the oil change, every 3,000 miles. True, the shop manuals for many cars say you can go much longer, but my feeling - shared by many automotive experts - is that you get longer and better service out of your car if you change the oil and do a grease job more frequently.

To grease the ball joints you'll need a grease gun and multipurpose grease, both available for a few dollars at auto parts stores. If the grease gun you buy doesn't come with a flexible hose, buy one. The hose is inexpensive, and it's the only way to reach some grease fittings on many cars.

Usually you'll have to raise the car to get underneath it and at the ball joints. Don't crawl under the car if it's supported only by a bumper jack: Use a jack stand under the lower control arm for support, or drive one or both wheels up on a sying grease, wipe old grease and dirt off each fitting with a rag - both so you can see the ball joint clearly and to avoid contaminating the new grease.

Now push the nozzle onto the nipple of each ball joint, pumping grease in with the grease gun. When you see the seal begin to bulge, you know you have applied enough grease. Move on to the next joint.

Remember that each front wheel has an upper and a lower ball joint. The lower ball joint is readily visible; the upper is often hidden and easy to miss. To avoid this, start with either wheel, grease its upper and lower ball joints, then work over to the other wheel, finishing with its upper ball joint.

While under the car, take the opportunity to look at the underbody for signs of damage or leakage. Also check the fluid level (battery, transmission, etc.), replenishing as necessary. When working under the car, it's a good idea to wear safety goggles. It's easy to knock accumulated grease andgrime off into your eyes.