To find the correct gap, you must consult your owner's manual. The information will be in the maintenance section, often within a section on spark plug replacement.
If you don't have the owner's manual, you can try:
* Searching online: Search for "[Your Chevy Model] [Engine Size] spark plug gap" (e.g., "1996 Chevy Silverado 5.7L spark plug gap"). Be sure to use the *exact* engine size.
* Checking a repair manual: A Haynes or Chilton repair manual for your specific vehicle will contain this information.
Attempting to guess the spark plug gap is strongly discouraged. An incorrect gap can lead to misfires, poor performance, and even engine damage.