If the CV joints need service, a CV joint service kit should be installed. Joint service kits typically include a CV joint, boot, boot clamps and seals, special grease for lubrication (various joints require different amounts of grease; the correct quantity is packed in each kit), retaining rings, and all other attachment parts.

Part manufacturers also produce a line of complete boot sets for each application, including new clamps and the appropriate type and amount of grease for the joint. CV joints require a special high-temperature, high-pressure grease. Substituting any other type of grease may lead to premature failure of the joint. Be sure to use all the grease supplied in the joint or boot kit. The same rule applies to the clamps. Use only those clamps supplied with the replacement boot. Follow the directions for positioning and securing them.

Old boots should never be reused when replacing a CV joint. In most cases, failure of the old joint is caused by some deterioration of the old boot. Reusing an old boot on a new joint usually leads to the quick destruction of the joint.

The photo sequence below shows the procedure for removing a typical drive axle and replacing a CV joint boot. Always refer to the your vehicle's service manual for the exact service procedure. The diagnosis and service chart shown below gives an idea of the types of front-wheel drivetrain problems that can occur.

The following are some guidelines to follow when servicing CV joints:

• Never jerk or pull on the axle shaft when removing it from a vehicle with tripod inner joints. Doing so may pull the joint apart, allowing the needle bearings to fall out of the roller. Pull on the inner housing, and support the outer end of the shaft until the shaft is completely out.
• Always torque the hub nuts to the vehicle manufacturer's specifications. This is absolutely necessary to properly preload the wheel bearings. Do not guess. The specifications can vary from 75 to 235 ft-lb (101 to 318 N∙m). Most axle hub nuts are staked in place after they have been tightened.

• Never use an impact wrench to loosen or tighten axle hub nuts. Doing so may damage the wheel bearings as well as the CV joints.
• On vehicles with anti-lock brakes, use care to protect the wheel speed sensor and tone ring on the outer CV joint housings. If misaligned or damaged during joint replacement, it can cause wheel speed sensor problems.
• Always recheck the alignment after replacing CV joints. Marking the camber bolts is not enough, because camber can be off as much as three-quarters of a degree due to differences between the size of the camber bolts and their holes.

Removing and Replacing a CV Joint Boot Removing the axle from the car begins with the removal of the wheel cover and wheel hub cover. The hub nut should be loosened before raising the car and removing the wheel. After the car is raised and the wheel is removed, the hub nut can be unscrewed from the axle shaft. The brake line holding clamp must be loosened from the suspension. The ball joint must be separated from the steering knuckle assembly. To do this, first remove the ball joint retaining bolt. Then pry down on the control arm until the ball joint is free. The inboard joint can be pulled free from the transaxle. A special tool is normally needed to separate the axle shaft from the hub. This allows the axle to be removed from the car. The axle shaft should be mounted in a soft-jawed vise for work on the joint. Pieces of wood on either side of the axle work well to secure the axle without damaging it. Begin boot removal by cutting and discarding the boot clamps. Scribe a mark around the axle to indicate the boot's position on the shaft. Then, move the boot off the joint. Remove the circlip and separate the joint from the shaft. Slide the old boot off the shaft. Wipe the axle shaft clean and install the new boot onto the shaft. Place the boot into its proper location on the shaft and install a new clamp. Using a new circlip, reinstall the joint on the shaft. Pack joint grease into the joint and boot. The entire packet of grease that comes with a new boot needs to be forced into the boot and joint. Pull the boot over the joint and into its proper position. Use a dull screwdriver to lift an edge of the boot up. This will equalize the pressure inside the boot with the outside air. Art courtesy of Delmar - Thomson Learning. Install the new large boot clamp and reinstall the axle into the car. Torque the hub nut after the wheels have been reinstalled and the car is sitting on the ground.