Why You Should Replace a Torn or Ripped Boot on a Ball Joint or Tie Rod End
You may go through some inspection forms that say a torn or ripped boot on a ball joint or tie rod end is grounds for replacement of the entire unit. What's the reason for this? It may look perfectly fine, there may be no play, but what we're talking about is the integrity of the joint and the internal surfaces.
If you hear the phrase full stud ball joint, that means it's a full ball at the end and it interacts with surfaces inside a sealed ball joint. These surfaces, they're not metal. A lot of them are a very highly engineered plastic that goes in there that controls the friction between the stud and also the ball itself.
Also, there is the lubricant inside. Once that lubricant is lost, it's lost for good and there's no way you're going to be able to pump it in with a syringe.
If you do see a busted boot on a ball joint or tie rod end it's grounds for replacement, but you have a choice when it comes to replacement parts.