Clutch Plates (508, 509)

The splines are worn or the plate is worn.

Thrust Washer (218)

Damaged or worn

Output Shaft (671)

The shaft or the splines are broken.

Seals

Cut or nicked

Checkball

Leaking

Piston (505)

Jammed, cracked, or damaged

Housing (504)

Cracked or damaged

Sun Gear (650)

Worn

Spring Assembly (506)

Jammed

Oil Feed

Plugged