jdreedchicagoll 5/7/2012go .040
bear.1216 9/4/2013Proper spark gap can be found on vehicle emmisions label under the hood. It is a white sticker attached under the hood. It lists emmision controls vacuum diagram and has engine info like engine size and tune-up settings like spark timing and gap.
Jimm 9/4/2013The correct gap for the Denso #4511 spark plug is: 0.040". Some plugs specifiy a 0.045" gap - such as the AC Delco # 6 plug - for this same engine and application; 5.3L 2002 Chevy Silverado.
The exact plug gap would depend in part, on the spark plug design and manufacturer - not all plugs will have the same gap specification - even for the same vehicle and engine.