Document ID# 2038440
2003 Chevrolet Chevy K Silverado - 4WD
Subject: Whine Noise In First And Second Gear - keywords acceleration case clash filter fluid oil #PIP3259H - (11/14/2007)
Models: 2002-2007 Chevrolet Avalanche
1999-2008 Chevrolet Express
1999-2007 Chevrolet Silverado, and Suburban
1999-2008 GMC Savana
1999-2007 GMC Sierra and Yukon XL
with 4L80E (RPO - MT1) or 4L85E (RPO - MN8)
This PI was superseded to update model years. Please discard PIP3259G.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
The 4L80E/4L85E automatic transmission may experience a condition of planetary gear whine noise in first and second gear. The planetary gear noise is typically louder in first gear as compared to second.
Recommendation/Instructions:
This planetary gear whine noise can be characteristic of the 4L80E/4L85E. The vehicle should be compared to an identically built vehicle (same GVWR) for comparison before attempting any repairs.
If it is determined that a vehicle has an abnormal amount of noise and the transmission was built after 9-01-03, perform the Rear Unit End Play Check (SI Document ID # 52027). The correct end play is between 0.127-0.508 mm (0.005-0.020 in).
If end play is out of specification, inspect and replace the output planetary gearset (661 - Output Carrier Assembly and 650 - Sun Gear) as necessary. Set rear end play between.005" -.020" using correct selective thrust washer (674). Target between.010"-.015".
If end play is within specification, transmission replacement is necessary, contact PQC for warranty authorization.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
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Document ID# 2038440
2003 Chevrolet Chevy K Silverado - 4WD
Hope this helps you! :)
Sunday, November 18th, 2007 AT 8:34 PM
