SPEED LOSS ON HILLS CRUISE REVISE HOSE ROUTING S/T TRUCK. GMC Truck S15 Pickup - 4WD 1983

For 1990-2009 cars

# SPEED LOSS ON HILLS CRUISE REVISE HOSE ROUTING S/T TRUCK

#### MODELS: 1983 S/T WITH LR2 2.8L V-6 AND L02 2.0L L-4 ENGINES

Some 1983 S/T trucks with LR2 2.8L V-6 and LQ2 2.0L L4 engines may lose in excess of 4 mph on long grades or hills. This condition is caused by insufficient engine vacuum and can be remedied by implementing the following changes:

L02 Engine

1. LQ2 engine with A/C and/or 4WD

A. Remove existing hose and cap tee (W-3)

B. Install new hose - route as shown (X-2)

C. Cut existing hose - install tee - attach hoses (Y-1)

2. LQ2 engine without A/C and/or 4WD

A. Remove existing hose and cap tee (W-3)

B. Install new hose - route as shown (X-2)

C. Remove existing fitting and install vacuum fitting - attach hose (Z-2-4*)

LR2 Engine

1. LR2 engine with A/C and/or 4WD

A. Remove existing hose and cap tee (W-3)

B. Install new hose - route as shown (X-2)

C. Cut existing hose - install tee (Y-1)

2. LR2 engine without A/C and/or 4WD

A. Remove existing hose and cap tee (W-3)

B. Install new hose - route as shown (X-2)

C. Remove plug in intake and install vacuum fitting - attach hose (Z-2-4*)

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.