The 2006 Chevy Cobalt base model came with a 2.2-liter in-line four-cylinder engine and a five-speed manual transmission. The constant velocity axle, also known as a CV axle or wheel drive axle, transfers rotation from the transmission differential to the front wheels. Each of the front axles have two CV joints that allow the axle to rotate over bumps, and changing terrain without binding or damaging the transmission. The most common sign of an imminent CV joint failure is a distinctive clicking noise when cornering often followed by a wobbly drive shaft, prior to complete failure. In order to repair the CV joint you have to replace the entire shaft, which will require a few special tools, but is well within the realm of the home mechanic.
Park the vehicle on a level surface and set the parking brake. Loosen the lug nuts on the wheel to be service with a lug wrench. Lift the front of the vehicle into the air with a floor jack and place jack stands under the front sub-frame rails. Lower the vehicle until it rests securely on the jack stands.
Remove the lug nuts and then remove the wheel from the vehicle. Instruct a helper to sit in the vehicle and apply the brakes. Loosen the axle spindle nut with a 30 mm socket and breaker bar; once loose instruct the helper to exit the vehicle. Disconnect the wheel speed sensor harness from the wheel speed sensor and position it aside.
Place a chisel on the end of the axle shaft and tap the chisel with a hammer to separate the axle splines from the wheel hub splines. Bend the lower ball joint cotter pins strait and then remove the cotter pin from the ball joint stud with a pair of pliers. Remove the ball joint nut with a socket and ratchet.
Separate the lower ball joint from the steering knuckle with a pry bar between the control arm and knuckle. Pull the steering knuckle towards the outside of the vehicle and remove the faulty axle from the wheel hub.
Install a drive shaft removal tool over the inner most tripod portion of the axle and tighten the nuts with a socket and ratchet. Thread a slide hammer tool into the axle removal tool. Slide the weight of the slide hammer to the end of the tool until the axle shaft separates from the transmission. Remove the axle shaft removal tool and slide hammer from the faulty axle and set them aside. Inspect the axle seal at the transmission for any wear or damage and replace as necessary.
Position the axle seal protector through the axle seal and into the transmission. Slide the new drive shaft into the transmission through the seal protector until the splines are fully concealed. Pull the axle seal protector tool out of the axle seal and from around the axle shaft. Push the axle shaft into the transmission until it is fully seated. Pull on the tripod slightly to ensure the axle is properly engaged to the transmission.
Pull the steering knuckle assembly towards the outside of the vehicle and guide the axle shaft into the hub, engaging the wheel hub splines. Push the steering knuckle back into place and pry the lower control arm down with a pry bar. Guide the lower ball joint stud into the steering knuckle and loosely install the castle nut.
Tighten the lower ball joint nut to 37 foot-pounds with a torque wrench. Loosen the ball joint nut 270 degrees and then tighten to 37 foot-pounds plus 30 degrees. Slide a new cotter pin through the castle nut and ball joint stud. Bend the cotter pin legs around the castle nut in opposite directions.
Install a new axle nut onto the axle shaft and wheel hub hand tight. Instruct a helper to sit in the vehicle and apply the brakes. Tighten the axle nut to 155 foot-pounds with a torque wrench and 30 mm socket. Instruct the helper to exit the vehicle.
Install the wheel and tire to the vehicle and install the lug nuts hand tight. Lift the front of the vehicle off the jack stands and remove the jack stands. Lower the vehicle to the ground. Tighten the lug nuts to 100 foot-pounds in a criss-cross pattern.
