Tahoe 2WD V8-6.0L Hybrid (2008)
Slip Yoke: Customer Interest
Drivetrain - Bump/Clunk Noise at Stop Or From Launch
TECHNICAL
Bulletin No.: 09-04-17-002E
Date: January 14, 2011
Subject: Bump Feel/Clunk Noise at Stop or from Launch (Clean/Lubricate Propeller Shaft Slip Yoke Splines)
Models:
2007-2008 Chevrolet Avalanche, Suburban
2007-2009 Chevrolet Tahoe
2007-2010 Chevrolet Silverado (New Body Style) with Single-Piece Propshafts
2007-2008 GMC Yukon XL
2007-2009 GMC Yukon
2007-2010 GMC Sierra (New Body Style) with Single-Piece Propshafts
All Equipped with 4L60 Automatic Transmission (RPO M30) and 2WD
Attention:
This bulletin contains a procedure to clean/lubricate the slip yoke splines and replace the slip yoke, if necessary. Check the history on this vehicle. If the
lubrication procedure has been performed previously, then continue on and replace the slip
yoke.
Supercede:
This bulletin is being revised to update the warranty statement. Please discard Corporate Bulletin Number 09-04-17-002D (Section 04 - Driveline/Axle).
Condition
Some customers may comment that the vehicle has a bump feel or a clunk noise at a stop or on launch. Customers may also comment that the bump feel
or clunk is noticed after the vehicle has come to a complete stop and that it feels as if the vehicle was bumped from behind.
Cause
This condition may be caused by a slip/stick condition in the interface between the rear propshaft slip yoke and the transmission output shaft splines.
Braking to a complete stop can force the propshaft slip yoke forward into the transmission while the vehicle rebounds slightly backward after stopping its
momentum and create this condition.
Correction
Note
Do not use the grease from this bulletin for lubrication of the slip yoke splines on 2WD MYC 6 Speed Transmissions or any 4WD vehicles. The output
shaft in a 2WD MYC 6 Speed Transmissions or a 4WD transfer case does not have a grease retainer to keep the grease from migrating into the
transmission or the transfer case and mixing with the fluid inside. The new grease is not compatible with the automatic transmission fluid (ATF) and can
cause damage if mixed. Please refer to Corporate Bulletin Number 09-04-21-003B for repairing the bump feel or clunk noise condition on 4WD
vehicles.
Note
A bump feel or noise may also be due to fuel movement in the fuel tank when not completely full. If the condition is eliminated after filling the fuel tank,
the noise is isolated to the fuel movement in the tank. Please make no repair attempts, as this noise is considered an operating characteristic.
Verify the customer's concern.
Clean/Lubricate Slip Yoke Splines
1. Remove the rear drive shaft. Refer to One-Piece Propeller Shaft Replacement in SI.
2. Inspect the rear slip yoke splines on the drive shaft.
3. Clean the slip yoke splines with brake cleaner or equivalent and a shop towel.
4. Assure the yoke is free of rust or other foreign material.
5. Lubricate the slip yoke spline with grease, P/N 19257121 (in Canada, 19257122), using a brush or swab to completely cover the entire spline with
a light coating of grease.
