For 1990-2009 cars

Cause | Correction
--- | ---
Drain and fill the unit with new oil with ultraviolet dye J 28431-6 before using the J 28428-E black light, when inspecting for leaks.
Restricted or damaged ventilation assembly | Replace the ventilation assembly, as required.
Worn, scored, or missing drain and/or fill plug sealing washers | Install new drain plugs and tighten the plugs per specifications.
Worn or damaged input or output shaft oil seal | Replace the output shaft oil seal, as required.
Cut or damaged output housing O-ring seal | Replace the O-ring seal, as required.
Worn internal shaft oil seals Worn or damaged internal shaft oil seals may be detected by a fluid leak at the vent hole area on the bottom of the cover. | Replace the oil seals, as required.
Worn or damaged right side axle shaft oil seal | Replace the axle shaft oil seal and axle shaft, as required.
Cut or damaged transaxle assembly-to-transfer case O-ring seals | Replace the O-ring seals, as required.
Cases or housings porosity or leaking seal surfaces | Replace the transfer case assembly if it cannot be repaired.