GM Truck Club
Founded in 2004 ~ We're the #1 Chevy Truck & SUV Forum.
Silverado & Sierra | Tahoe & Yukon | Suburban & Yukon XL | SUV & CROSSOVER
Results 1 to 2 of 2
  1. #1

    Join Date
    Feb 2008
    Red Wing, Minnesota, United States

    Default .060 vs .040 gap for vortec 5.7

    Over the years I have read alot of talk about GM putting out a bulletin for the Vortec 5.7 going from a .060 to a .040 gap for the spark plugs. Yet when i search google or yahoo i cant find anything except what sends me back to this site. So, I need to put in new spark plugs on my beast and am wondering should Istick with the factory gap that the spark plugs are set to or adjust them to .040 as to what I have read alot of guys doing on this site. So what are REAL WORLD results form the gap change if any? Less hesitation, better MPG, longer or shorter spark plug life?????? Also, will adjusting these not so cheap spark plugs from a .060 to a .040 actaully cause premature wear on the spark plug itself.
    99 K1500 Suburban LT "THE BEAST"
    Hypertech III, K&N, true dual

  2. #2
    Caddiac's Avatar
    Join Date
    May 2011
    Upstate South Carolina
    Blog Entries


    I have no personal experience with changing the gap to .040. I have been running the standard .060 gap and the plugs look good after 100,000 miles. my guess would be that there would be a loss of performance if anything.
    86 911 Porsche Carrera
    98 K1500 Suburban LT
    2012 Nissan Leaf

    ​General Motors.
    Because life is too short to drive a Ford

Similar Threads

  1. T56 In a 96 1/2 ton 350 Vortec 4wd???
    By Erik3621 in forum GM Powertrain
    Replies: 4
    Last: 02-27-2010, 10:55 PM
  2. 5.7L vortec ?????
    By cpon2009 in forum GM Powertrain
    Replies: 5
    Last: 02-19-2010, 08:21 PM
  3. V6 Vortec?
    By Lightzz2k in forum Chevy C/K Truck Forum
    Replies: 6
    Last: 11-19-2009, 11:14 PM
  4. Vortec 383 What Cam to use
    By OleBlue97 in forum Performance & Fuel
    Replies: 1
    Last: 05-28-2009, 08:35 PM
  5. New Vortec Max
    By 07Vmax in forum Performance & Fuel
    Replies: 4
    Last: 05-11-2009, 12:49 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts