spark plug gap on K2 trucks

fondupot · October 25, 2014

Anyone know if the spark plug gap is different for the k2 motors vs previous years?

Previous years gap was .040 for the 5.3L. Is that the same for the Direction Injected EcoTec3 motors?

SouthernSilveradoGuy85 · October 25, 2014

I can't remember what it is, but it should say it on the radiator shroud.

TJay74 · October 25, 2014

It will be listed on the emissions sticker under the hood. I don't know right off hand.

gone_fishing · October 25, 2014

Owners manual says 0.037"-0.043"

fondupot · October 25, 2014

Thanks guys, I was too lazy to go look at the truck last night when I posted this.

I think I am going to be checking the gaps on my plugs here soon.

Whats better for the DI motor? To be on the smaller gap size or the higher gap size? or .040 right in the middle?

TJay74 · October 25, 2014

If I remember right, used to be larger for N/A motors and on the smaller side for boosted motors. Idea was a boosted motor could blow out the spark if the gap was too big.

redwngr · December 3, 2014

I'd aim for middle spec (0.040")

MikeNH · December 3, 2014

Most new plugs are not supposed to be adjusted. It can damage them. Pretty sure there is a TSB for this.

redwngr · December 3, 2014

Most new plugs are not supposed to be adjusted. It can damage them. Pretty sure there is a TSB for this.

I like to check them, but rarely find one off centre spec.

KARNUT · December 3, 2014

They don't go 100k miles anymore? The last truck I had pass 100k miles the plugs were sill going at 180K mostly HWY miles.

bladz1454 · December 3, 2014

They don't go 100k miles anymore? The last truck I had pass 100k miles the plugs were sill going at 180K mostly HWY miles.

With the amount of oil being dumped on plugs with new GDI motors, highly doubtful.

MikeNH · December 3, 2014

I like to check them, but rarely find one off centre spec.

You can check them but I'm pretty sure you won't be able to adjust gap.

redwngr · December 4, 2014

I was talking plugs in general (as opposed to these DI engines specifically) Are these not adjustable for some reason?

With todays' plug life, we don't handle them anywhere as often as in the past.

Diesel trucks reduces exposure as well

MikeNH · December 4, 2014

I was talking plugs in general (as opposed to these DI engines specifically) Are these not adjustable for some reason?

With todays' plug life, we don't handle them anywhere as often as in the past.

Diesel trucks reduces exposure as well

To the best of my knowledge it's been that way for a while I seem to recall the plugs I did on my 2003 being non-gappable (new word right there haha).

See post #8:

http://www.gm-trucks.com/forums/topic/110267-setting-gap-on-spark-plugs/