Transfer Case Leak Diagnosis

WARNING: This page is about a different car, the 2004 Pontiac Vibe. However, it is still accessible from the selected car via links, so may be relevant.

Cause	Correction
GM P/N United States 12378514, GM P/N Canada 88901045 Hypoid Gear Oil has ultraviolet dye already included within the oil. Drain and fill the unit with new oil before using the black light, when inspecting for leaks. Ultraviolet dye is not approved for continued use.
Restricted or damaged breather plug assembly	Replace the breather plug as required.
Worn, scored, or missing drain and/or fill plug sealing washers	Install new sealing washers and tighten the plugs per specifications.
Worn or damaged driven shaft oil seal	Replace the driven shaft oil seal and output flange as required.
Cut or damaged drive shaft housing O-ring seal	Replace the O-ring seal as required.
Worn wheel drive shaft oil seals Worn or damaged wheel drive shaft oil seals may be detected by a fluid leak at the breather plug area on the bottom of the case. A red colored fluid indicates a transaxle fluid leak and a clear or brown colored fluid indicates a hypoid gear oil leak.	Replace the oil seals and the drive/driven shafts as required.
Cut or damaged transaxle assembly-to-transfer case seal	Replace the seal as required.
Cases or housings porosity or leaking seal surfaces	Replace the cases and housings as required and reseal the assembly.