CV boot: Achilles' heel of Mazda drivetrain

Anthony Fontanelle
October 2, 2007

The suspension setting of every Mazda model with front- or four-wheel drives is designed to transmit the rotational motion from the engine to the drive shaft while enabling the wheels to turn. It has to enable the wheels to steer the car at the same time that engine power is being transferred at different angles. Compared to the rear suspension setting of the Mazda drivetrain, the steered wheels of the car is linked to the drive shaft through a specialized coupling called constant velocity or CV joint. Mazda CV joints are the rubber-encased billet at the end of the shaft barrel. They are held in place by a circlip and shielded from road salt and degreasing by a Mazda CV boot. Inside the rubber are ball bearings and bushings that engage the shaft barrel every time it flows torque. At the other end of the Mazda CV joint are the network of clamps and gears that lead to the drive wheels.

There are two most commonly used types of Mazda CV joints: ball-type and tripod-type CV joints. Different variations of ball-type Mazda CV joints are used on the outer side of the drive shaft, where more torques are inflicted on the chassis, while tripod-type Mazda CV joints are mostly used at the inner side of the drive shaft. They hardly require any maintenance and are supposed to last very long provided that the protective CV boot will not get damaged. Once the Mazda CV boot is torn apart, the grease comes out and the moisture and dirt come in, eventually causing the CV joint to fail due to lack of lubrication and corrosion. When a damaged boot surfaces early, simply replacing the Mazda CV boot and repacking the CV joint with fresh grease can fix the problem. If the Mazda is still ran with broken CV boots, the CV joint or the whole drive shaft stands to get broken. In worst cases, the CV joint may disjoin, ruining the drivetrain setting of the car from the suspension system to the transmission system.

Source:  Amazines.com