Your vehicle has performed flawlessly throughout your daily commuting over the past several years. However, you're now hearing a clicking noise every time you turn your steering wheel--a definite sign of a torn constant velocity axle boot. Although your worn constant velocity axle doesn't necessarily pose a risk to your safety, it should be replaced to ensure consistent driving performance. Follow these steps to replace it in just a couple hours:

Identify Your Damaged Axle

Your vehicle will have either two or four constant velocity axles depending on its drivetrain. However, your vehicle's clicking noise indicates that one of your front axles has sustained a torn boot. You must identify which of your front axles is damaged before you're able to purchase a compatible replacement axle.

Your front axles are prone to developing torn boots since they're subjected to steering wear. For this reason, you should always inspect your front axles first--even if your vehicle is four-wheel drive and uses four constant velocity axles.

You can determine which one of your axles require replacement simply by locating the torn or missing boot. Depending on the design of your engine bay, you may be able to see your torn boot by simply opening your hood and looking straight down your bay. However, in most cases, you'll need to use a hydraulic jack to lift your vehicle before you're able to visually inspect your axle boots. If you must crawl beneath your vehicle to see your axle boots, then place jack stands or wheel ramps beneath your vehicle before doing so to ensure your safety.

Once you've determined which axle needs to be replaced, you can purchase a compatible replacement axle from your local auto parts store or vehicle manufacturer.

Remove Your Damaged Axle

Break loose the nuts that secure the tire attached to the end of your damaged axle. Jack up the end of your vehicle that must receive the replacement axle and place jack stands underneath your vehicle's safe lifting points. Once your damaged axle no longer bears any weight, finish removing the lug nuts from your wheel and set aside your tire.

Now that you have access to your axle's wheel hub, use pliers to straighten the bent ends of your hub's cotter pin and pull the pin out of your axle. Once your cotter pin is removed, you can use the appropriate socket (which will differ for each vehicle) to remove your axle nut from the center of your rotor. If you have trouble identifying the socket that's required to remove your axle nut, consult your vehicle's service manual or manufacturer.

Once your axle nut is removed, separate your brake caliper from your rotor by removing the bolts from your caliper's mounting bracket. To allow for easier removal and replacement, you should also remove the bolts that secure your tie rod to your wheel assembly. For most vehicles, this only requires the removal of one or two bolts from the interior side of your assembly.

With your caliper and tie rod removed from your wheel hub, turn your steering wheel so that your dismantled wheel assembly faces slightly away from your vehicle. Pull the assembly away from your vehicle to allow the end of your axle slide out of your wheel hub. If necessary, hit the end of your axle with a rubber mallet to further "convince" it to separate from your wheel hub.

Once your axle is out of your wheel hub, you can use a large, flat screwdriver or pry bar to pull the other end of your axle out of your transmission. Depending on your vehicle's make and model, some transmission fluid may leak through your axle's joint. Place a drain pan beneath your transmission to ensure that any leaking fluid is contained.

Install Your Replacement Axle

Place a small amount of transmission fluid around the ring on the end of your axle that will be inserted into your transmission. Push the end of your replacement axle into your transmission until it loudly clicks into place. Although you can typically accomplish this task without any tools, you may need to firmly tap the wheel end of your replacement axle with your mallet until the axle pops into your transmission.

Once your axle is connected to your transmission, simply reverse the steps you performed while dismantling your wheel assembly to finish the job.

Test Your Work

Lower your vehicle off your jack stands and give your vehicle a short (and slow) test drive around your neighborhood to ensure you replaced your constant velocity axle correctly. If your vehicle does not operate correctly, then stop immediately and have your axle inspected by an auto repair professional.