Illuminate the anthers on the left and right and check their integrity, paying attention to traces of grease on the cuffs and nearby.
If the boot is damaged, replace the corresponding joint with boot for safety. Penetrating moisture will definitely destroy the joint.
Check the reliability of the fastening of the nut and the joint cotter pin, but do not overtighten the nut.
The original material is here [MitsubishiMan.ru]