Leak at Front Slip Yoke

WARNING: This page is about a different car, the 2010 GMC Sierra, 2010 GMC Cab & Chassis Sierra, 2010 Chevrolet Silverado, and 2010 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

Checks	Action
DEFINITION: A few drops of lubricant that are leaking from the splined yoke are normal. This condition does not require attention.
The slip yoke barrel is burred, nicked, corroded, or worn or the welch plug is leaking.	Inspect the slip yoke for burrs. Careful use of crocus cloth or fine stone honing can remove minor burrs. If the yoke is badly burred, corroded, or worn, replace the yoke. If the welch plug is leaking replace the yoke. Refer to Propeller Shaft Slip Yoke Replacement . Replace the oil seal. Refer to one of the following procedures: For vehicles equipped with the BW 4485-NR3 transfer case, refer to Rear Output Shaft Seal Replacement . For vehicles equipped with the MP 1222/1225/1226-NQG transfer case, refer to Rear Output Shaft Seal Replacement . For vehicles equipped with the MP 1625/1626-NQF transfer case, refer to Rear Output Shaft Seal Replacement . For vehicles equipped with the MP 3023/3024-NQH transfer case, refer to Rear Output Shaft Seal Replacement . For vehicles equipped with the 4L60-E automatic transmission, refer to Propeller Shaft Front Slip Yoke Oil Seal Replacement . For vehicles equipped with the 6L50/6L80/6L90 transmission, refer to Transmission Output Shaft Seal Replacement (Four Wheel Drive) . For vehicles equipped with the Allison transmission, refer to Rear Propeller Shaft Seal Replacement .
There is a faulty oil seal in the transmission or in the transfer case output shaft.	Replace the oil seal. Refer to one of the following procedures: For vehicles equipped with the BW 4485-NR3 transfer case, refer to Rear Output Shaft Seal Replacement . For vehicles equipped with the MP 1222/1225/1226-NQG transfer case, refer to Rear Output Shaft Seal Replacement . For vehicles equipped with the MP 1625/1626-NQF transfer case, refer to Rear Output Shaft Seal Replacement . For vehicles equipped with the MP 3023/3024-NQH transfer case, refer to Rear Output Shaft Seal Replacement . For vehicles equipped with the 4L60-E automatic transmission, refer to Propeller Shaft Front Slip Yoke Oil Seal Replacement . For vehicles equipped with the 6L50/6L80/6L90 transmission, refer to Case Extension and Gasket Replacement . For vehicles equipped with the Allison transmission, refer to Rear Propeller Shaft Seal Replacement .