| Subject: | 4L60-E Automatic Transmission Oil Pump First And Second Design
Identification |
| Models: | 1997-2002 Chevrolet Camaro |
| 1997-2002 Pontiac Firebird |
| 2002-2004 Cadillac Escalade, Escalade EXT |
| 1997-1999 Chevrolet C/K Full Size Pickup |
| 1997-2004 Chevrolet Astro, Blazer, Corvette, Express, S-10, Suburban |
| 1999-2004 Chevrolet Silverado |
| 2000-2004 Chevrolet Tahoe |
| 2002-2004 Chevrolet Avalanche, TrailBlazer |
| 2004 Chevrolet Colorado, SSR |
| 1997-2004 GMC Envoy, Safari, Savana, Sierra, Sonoma |
| 2000-2004 GMC Yukon, Yukon XL |
| 1997-2004 Oldsmobile Bravada |
| with 4L60-E Automatic Transmission (RPOs M30, M32, M33) |
The purpose of this bulletin is to identify the correct oil pump rotor (212)
and slide (203) usage for the two different transmission oil pump designs.
Manufacturing of the first design oil pump rotor (212) and slide (203)
ended November 30, 2000.
Manufacturing of the second design oil pump rotor (212) and slide (203)
began December 1, 2000.
Important: It is critical that the first and second
design oil pump rotors and slides do not become intermixed. Do not use first design
pump components with second design pump components. If the pump components from either
design are intermixed, pump efficiency will be affected resulting in less than optimal
pump performance.
The first design oil pump rotor (212) and slide (203) DO NOT have
any identification markings.
The second design oil pump rotor (212) and slide (203) are identified
with dimples (circular depression) as shown above.
The rotor (212) has two dimples adjacent to the rotor drive tangs (1).
The slide (203) has one dimple located on the spring tab (2).
