For the 4.3L V6 engine, the spark plug gap is 0.035 - 0.045 inches.
For the 4.8L V8 engine, the spark plug gap is 0.045 inches.
For the 5.3L V8 engine, the spark plug gap is 0.045 inches.
For the 6.0L V8 engine, the spark plug gap is 0.045 inches.