Leak at Front Slip Yoke

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2004 Oldsmobile Bravada, 2004 GMC Envoy XUV, 2004 GMC Envoy XL, 2004 GMC Envoy, and 2004 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.

Checks	Action
DEFINITION: An occasional drop of lubricant leaking from the splined yoke is normal and requires no attention.
The slip yoke barrel is burred, nicked, corroded, or worn.	Inspect the slip yoke for burrs. Minor burrs can be removed by careful use of crocus cloth or fine stone honing. If the is badly burred, corroded or worn, replace the yoke. Replace the oil seal. Refer to one of the following: Transfer Case Output Shaft Seal Replacement - Rear in Transfer Case - NVG 126-NP4 Transfer Case Output Shaft Seal Replacement - Rear in Transfer Case - NVG 226-NP4 Transmission Extension Housing Rear Oil Seal Replacement in Automatic Transmission - 4L60-E
There is a faulty transmission or transfer case output shaft oil seal.	Replace the oil seal. Refer to one of the following: Transfer Case Output Shaft Seal Replacement - Rear in Transfer Case - NVG 126-NP4 Transfer Case Output Shaft Seal Replacement - Rear in Transfer Case - NVG 226-NP4 Transmission Extension Housing Rear Oil Seal Replacement in Automatic Transmission - 4L60-E