The rubber rots and swells because of dumbass mechanics using bearing grease on them.
This is the reason why you need to only use silicone grease on these parts.
You wont just need that rubber bit, you would also need the boots you see in the picture as they would be rotten too.
Now that you have to face such expense and know the reason for its failure, dont let this simple mistake of mechanic cost you again.
