For 1990-2009 cars

# CAMSHAFT-OIL GROOVE IN FROM CAMSHAFT BEARING

#### VEHICLES AFFECTED: 1986 'A, C, G, H, E, N' Models With 3.OL (VIN Code L) and 3.8L (VIN Codes A, B, 3, 7)

The oil groove in the front camshaft bearing journal has been removed from the camshaft on the above engines. It is now cast into the block behind the front cam bearing insert. This was done to improve front cam bearing load characteristics and longevity of the camshaft and bearing.

Some early 1986 engines were built, however, using camshafts with the groove still in them. If replacement of a camshaft on a 1986 engine becomes necessary for any reason, the one supplied by GM Parts may or may not have a groove in it. Also, the one in the vehicle may or may not have a groove in it.

For 1986, because the oil groove is now behind the cam bearing, either shaft can be used, but they are not interchangeable on 1985 and older models.

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.