So i bought a set of iridiums for my truck. sticker inside the hood says .060 gap. The plugs i bought came at .034. what now?

 

For your 99 Silverado with the 5.3L engine to run best, you must replace the spark plugs using the ACDelco 41-962 Double Platinum spark plug which comes pre-gapped at 0.040". The factory recommended gap for that engine is 0.040". You should not have to re-gap the ACDelco 41-962. If the gaps are not correct, take them back and get new plugs. Changing the gap can damage the platinum coating and can result in a plug going bad prematurely.

Using a spark plug other than the ACDelco 41-962 can result in driveability and performance problems.

I believe the sticker is wrong.

Wait a minute. There are essentially 2 different Chevrolet 1500 pickups for the 1999 model year. There is the early 1500 C/K Pickup which comes with either a 5.0 lor a 5.7 L engine. and then there is the 1500 Silverado Pickup which comes with either a 4.3L V6, a 4.8L V8, or the 5.3L V8. They are different animals!

What is the VIN code for the engine in your pickup?

 

Its a T motor. 5.3L Multi port fuel injected. .It's not a C/K model. Ive had issues with finding parts due to that discrepancy. Sticker in hood says gap of .060 and its correct. I've already fixed the issue by returning the cheap *** Chinese plugs with Bosch double platinum 8102 that came at .060. Was missing on first start up until i stupidly realized i forgot to plug the #7 coil in. Runs like a Swiss watch now. I thank you for your time. Chris