No way to fix anything without opening it up. If it is that bad pull it out and split the case.
They are not very complicated but the individual parts add up quickly.
No solutions I know if without taking it apart.
There is a great video by Crown Automotive on the case for an SYE install but will get you a ton if info. YouTube search YJ SYE.
89 2.5 TBI, 4" RC lift, 1" Booms, SYE, Adams Driveshafts front and rear, Ford 8.8 with 4:88s, BFG 33X12.50X15, and a ton of other stuff.
AF Jeep Club Tail Number 184