Ball Joint-Lower and Upper


Pivot points such as tie rod ends, ball joints, and constant velocity (CV) joints, are sealed with rubber boots.

Pivot points are sealed with rubber boots. Courtesy of Chrysler Corporation.

Joints with boots are usually permanently sealed, but there are many older cars and newer light trucks that still have fittings provided for lubrication. To be certain, always check the lubrication chart showing lube points for the vehicle.

The location of lube fittings is found in shop service manuals. Courtesy of General Motors Corporation, Service Technology Group.

Look carefully at the joint's boot. a damaged boot or joint seal will allow lubricant to leak out and allow dirt to enter and contaminate the lubricant. if the boot is damaged, the ball joint should be replaced. if no boot damage is evident, gently squeeze the boot. if the boot is filled with grease, it will feel somewhat firm. if the joint has a grease fitting and appears not to be filled with grease, use a grease gun and refill the joint. fill the joint until fresh grease is seen flowing out of the boot's vent. if too much grease is forced into the joint or it is forced in too quickly, the boot can unseat or tear.