WHITE SMOKE FROM EXHAUST AFTER EXTENDED IDLE

VEHICLES AFFECTED: 1986 AND 1987 S/T TRUCKS WITH 2.8L V6 ENGINE AND FEDERAL EMISSIONS

THIS BULLETIN IS PENDING PARTS AVAILABILITY, YOU WILL BE ADVISED WHEN PARTS ARE AVAILABLE.

Some 1986 and 1987 S/T trucks with 2.8L V6 engines and Federal Emissions may exhibit a blue/white smoke from the tailpipe after an extended idle.

To repair this condition, check the truck for loss of coolant or excessive use of oil and repair as necessary.

In addition, install a new service PROM using the following procedure:

A). Connect scan tool to ALCL connector and read PROM I.D.. If the PROM I.D. is one of the following numbers the truck already has the latest PROM, (8541, 8542, 8543, 8544 and 8545).

B). If the truck does not have the latest service PROM install one of the following PROMS:

Service PROM Application *

Model Model Transmission Axle Service Year PROM ---- ----- ------------- ----- ----

86/87 Sl0/Tl0 M4 All 1228541

86/87 Sl0/Tl0 M5 3.73 1228542

86/87 Sl0/Tl0 M5 4.11 1228543

86/87 S10 A4 All 1228544

86 T 10 A4 3.73 1228545

87 T 10 A4 3.73 1228544

86/87 T 10 A4 4.11 1228545

* 2.8L 1986/87 Federal Sales applications only.

Use applicable labour time and operation numbers.

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.