SERVICE MANUAL UPDATE SEC. 6A ENGINE MOUNT TIGHTENING SPEC.

SUBJECT: SERVICE MANUAL UPDATE - SECTION 6A - 3.1L V6 ENGINE FASTENER TIGHTENING SPECIFICATIONS (CORRECTED)

VEHICLES AFFECTED: 1990-92 'A AND W' CARS

The following changes should be made to your copies of these Service Manuals.

Year Division Section Page ----- --------- ---------- ------ 1990 Chevrolet Celebrity 6A4 6A4-44, 45 and Pontiac 6000

1990 Chevrolet Lumina 6A5 6A5-46

1990 Pontiac Grand Prix 6A5 6A5-49 Oldsmobile Cutlass Supreme Buick Regal

1991 Pontiac 6000 6A4 6A4-53

1991 Chevrolet Lumina 6A5 6A5-59 Pontiac Grand Prix Oldsmobile Cutlass Supreme Buick Regal

1992 Chevrolet Lumina 6A5 6A5-58 Pontiac Grand Prix Oldsmobile Cutlass Supreme Buick Regal

In the 1990 Chevrolet Celebrity and Pontiac 6000 Service Manuals, the fastener tightening specifications listed below should read as follows:

Engine Mount to Frame Nut 45 N.m (33 ft. lbs.). Engine Bracket to Engine - Large Bolt 110 N.m (81 ft. lbs.). Engine Bracket to Engine - Small Bolt 80 N.m (59 ft. lbs.). Rocker Arm Nut 24 N.m (18 ft. lbs.).

In the 1990 Chevrolet Celebrity and Pontiac 6000 Service Manuals, the figure references listed below should read as follows:

Cylinder Head Bolt Figure 22 Front Cover Bolt Figure 18 Intake Manifold Bolt Figure 10

In the 1990 Chevrolet Lumina, Pontiac Grand Prix, Oldsmobile Cutlass Supreme and Buick Regal Service Manuals, the fastener tightening specification for the Rocker Arm Nut should read 24 N.m (18 ft. lbs.).

In the 1990 Pontiac Grand Prix, Oldsmobile Cutlass Supreme and Buick Regal Service Manuals, the Front Cover Bolt figure reference should read Figure 20.

In the 1991 Pontiac 6000 Service Manual, the fastener tightening specifications should read as follows:

Engine Mount to Frame Nut 45 N.m (33 ft. lbs.). Engine Bracket to Engine Mount Nut 45 N.m (33 ft. lbs.). Rocker Arm Nut 24 N.m (18 ft. lbs.). Valve Cover Bolt 10 N.m (89 in. lbs.).

In the 1991 Pontiac 6000 Service Manual, the figure references listed below should read as follows:

Cylinder Head Bolt Figure 27 Front Cover Bolt Figure 23 Intake Manifold Bolt Figure 15

In the 1991 Chevrolet Lumina, Pontiac Grand Prix, Oldsmobile Cutlass Supreme and Buick Regal Service Manuals, the fastener tightening specifications listed below should read as follows:

Engine Mount to Frame Nut 45 N.m (33 ft. lbs.). Engine Bracket to Engine Mount Nut 45 N.m (33 ft. lbs.). Rocker Arm Nut 24 N.m (18 ft. lbs.). Valve Cover Bolt 10 N.m (89 in. lbs.).

In the 1991 Chevrolet Lumina, Oldsmobile Cutlass Supreme and Buick Regal Service Manuals, the figure references listed below read as follows:

Cylinder Head Bolt Figure 28 Front Cover Bolt Figure 24 Intake Manifold Bolt Figure 16

In the 1992 Chevrolet Lumina, Pontiac Grand Prix, Oldsmobile Cutlass Supreme and Buick Regal Service Manuals, the fastener tightening specifications listed below should read as follows:

Engine Mount to Frame Nut 45 N.m (33 ft. lbs.). Engine Bracket to Engine Mount Nut 45 N.m (33 ft. lbs.). Rocker Arm Nut 24 N.m (18 ft. lbs.). Valve Cover Bolt 10 N.m (89 in. lbs.).

The valve lash adjustment procedure should be used after reconditioning a valve seat when a new adjustable rocker arm stud has been installed. The fastener tightening specification for an adjustable rocker arm stud is 62 N.m (46 ft. lbs.).

Please note these changes in the appropriate Service Manuals.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those 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 a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.