FRT. ROCKER ARM SHAFT SUPPORT BOLT - REVISED IDENTIFICATION

SUBJECT: FRONT ROCKER ARM SHAFT SUPPORT BOLT

MODELS: 1986-1987 W4 FORWARD MODELS

The 1986-1987 W4 Service Manual improperly states that an oil groove exists in the front rocker arm shaft support bolt. The front rocker arm bolt is identical to the other rocker arm support bolts. Oil is supplied to the valve train components through an oil passage in the front rocker arm shaft support. Because of this, the information under the

"Important" symbol on Page 6A6-20 of the above mentioned service manual must be disregarded.

To properly reflect this information, Figures 1 and 2 of this bulletin should be substituted for Figures 19 and 23 on Pages 6A6-18 and 6A6-20 of the 1986-87 W4 Service Manual.

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.