There could be several answers to that question depending on optional equipment.
1997 Chevrolet Truck C1500 1/2ton P/U 2WD 5.0L SFI 8cylThe Spark Plug Gap.060 (In thousandths of an inch)
.060
.060
.060" for platnium
.060
.060
.060
.060
2005 Chevrolet Truck Express 1500 Van 2WD 4.3L SFI OHV 6cylThe Spark Plug Gap.060 (In thousandths of an inch) 2005 Chevrolet Truck Express 1500 Van 2WD 5.3L SFI 8cylThe Spark Plug Gap.040 (In thousandths of an inch)
.060
On the 3.3 Liter V6 it is .060.
5.3 Engine is .060