Engine - Roller Rocker Arms vs, Ball & Pivot Rocker Arms
File In Section: 6 - EngineBulletin No.: 57-61-35
Date: December, 1995
INFORMATION
Subject:
Roller Rocker Arms vs Ball and Pivot Rocker Arms
Models:
1995-96 Buick Century, Regal, Skylark
1996 Chevrolet Beretta, Corsica, Lumina, Monte Carlo
1995-96 Oldsmobile Cutlass Ciera, Cutlass Supreme, Achieva
1995-96 Pontiac Grand Prix, Grand Am with 3100 V6 Engine (VIN M - RPO L82)
Figure 1 - roller rocker arm:
Figure 2 - conventional ball and pivot rocker arm:
Approximately 4000 1995 A/N cars were built with roller rocker arms. All other 1995 3100 V6 engines were built with the conventional ball and pivot type rocker arm. For 1996 the 3100 V6 engine can be manufactured with either roller rocker arms or ball and pivot type rocker arms. Figure 1 shows a roller rocker arm as compared to Figure 2 which shows a conventional ball and pivot rocker arm. You should not mix rocker arm types on the same engine. It will be necessary to determine which type of rocker arm design the engine was manufactured with when servicing the cylinder head valve train components. GMSPO has service parts released for both design types.