Hey i have a 08 sierra denali with the 6.2 engine, just wanted to check to see what plugs are you all running in your engines? I have been told that the oe plug is good, i noticed some of the performance shops suggesting ngk, i used the e3 plugs in my other vehicles, what is you all take on this. It has 82,000 miles on it.

 

Isn't NGK's what is in there stock? I know all the gm's I have seen use them from the get.. Stock is fine..

 

E3 = crap in GM

 

Your factory plugs should be either AC Delco, NGK, or some sort of combo of the both. I've seen trucks with NGK's on one bank and Delco's on the other, as well as pics of plugs that have both NGK and Delco markings on them...IIRC. You have iridium plugs by the way, which last a very long time on a properly tuned engine...100K shouldn't be a problem. When the time comes, I'd go for stock factory replacements

This man speaks the truth...I don't know what engines E3 plugs do work in, but definitely not anything that the General makes....

 

I ran some e3 plugs in my built lt1 and they did well actually. But i noticed that there was an ac delco plug as well as the irridium
tr55ix plug. I know that these engines are supposed to be 100,000 miles before tune ups, but the previous owner did a goods bit of driving, as this truck had 82000 miles when i purchased it last month. Figuring with this type of milage it has to be highway type miles but it clearly has a miss when, and i am hoping it is as simple as a bad plug or two, i may even spurge for a set of wires as well.

 

Just for kicks i was watching the powerblock where horsepower tv tested these e3 plugs in a ls engine and it made more power with less fuel consumption which generally means a more efficient plug, so what is it about them, do they not last long, or have you all just had a bad experience with them?

 

Stroker just think about it, E3 sponsored that show, those guys will say anything if the dough in their pocket is right! The guys aren't experts. Remember just a couple weeks ago when the dude on Extreme 4X4 was talking about 3-valve ls heads, and 90# of fuel pressure???????

 

Personally, wrenching through the years, the only cars that I've worked on that Bosch products sorta work in are Volkswagons, just my personal experience. I've heard multiple times of guys installing E3 plugs in their rides just to pull them out as the engine ran like poop and got poor fuel economy with those plugs in it. Had a Toyota customer once who put some sort of Bosch platinum plugs in his Camry and afterwards it wouldn't start (dipshit had it towed in too, instead of just trying to put the original tune up parts back in that were working before)...threw in some cheap copper Denso plugs that the mid 80's Camry called for and it fired right up...

 

exactly the reason to trust what the more experienced people on here say over what a sponsored program is getting paid to say. i love powerblock with my weekend morning coffee lol, but no e3 plugs will go near my truck

 

I love the powerblock too, but it can turn into a big commercial some times, you can't go by the results that they come up with on those shows...their sponsor's products always seem to work well, according to them