Spark plugs?

[Sizzle55]

My 08 is just hit 103k and I was wondering what replacement plugs you guys would recommend. I also plan on cleaning the throttle body this weekend so if you guys have any pointers just let me know. thanks.

 

[Best4x4]

Autolite XP Iridium's have worked well in both my I5 & V8 H3's.

 

[odwah]

I got the OEM Delco Iridiums, so far so good. Throttle body is a piece of cake - just remove the Vortec air box, and then its four bolts on the body, a wire harness, and a hose. Spray away with your cleaner, and wipe off all the carbon/grime. I would recomend doing your MAF sensor as well, just ask for it at the parts store, they'll know what to grab.

 

[alrock]

AC Delco Iridium. Your first ones were good for 100K miles, not sure you're really going to see any improvements with others. Stay way from E3 with these trucks as owners have had significant issues with them.

 

[SedonaBound]

AC Delco Iridium. Your first ones were good for 100K miles, not sure you're really going to see any improvements with others. Stay way from E3 with these trucks as owners have had significant issues with them.

+1.

 

[digglesworth]

Pick up some maf cleaner and spray that off while youre cleaning your throttle body too. Disconnect the battery while you do this so the pcm can "relearn" the new air flow once everything is clean again.
And +1 on the ac delco plugs.

 

[deserth3]

Oem plugs.
X2 on staying away from E3.

Sent from my SAMSUNG-SM-G900A using Tapatalk

 

[Best4x4]

The Autolite Iridium XP's are made to OEM specs. They're not a performance plug, but an OEM replacement. Any plug with the same specs as the OEM requirement will be perfectly fine. In my personal experience I'd stay away from Bosch (they foul up extremely easy), and those snake oil plugs like the E3's or Splitfires.

Normally all Platinum or Iridium Plugs are good for 100K. It's the old Copper Core Plugs that don't last to 100K.

I went with the Autolite Iridium XP's for two reasons. #1 I've had nothing but great results with them in all the vehicles I've used them in, and #2 my local parts store didn't have the AC Delco's in stock.

OEM parts are fine, but we use plenty of none OEM parts on our H3's with zero issues. Like tires, fan belts, batteries, air filters, oil filters, oil, and brakes just to name a few. I am not afraid to use none OEM parts. So far I've used a Silla Radiator, Power Stop Rotors/Pads, BWD Sensors (on the I5), and both my Hummers are running extremely well with zero mechanical issues due to aftermarket parts. Like I said as long as the part is made to exact OEM specs = shouldn't cause any issues at all.

 

[alrock]

Best, how do you verify that all of the aftermarket parts you buy are made to "exact OEM specs"? I buy a lot of aftermarket too but I don't put a lot of faith in the various manufacturer statements when they simply say that they are OEM equivalents. How can you validate that the internals of a spark plug = OEM, or that the plastic sleeve on a ball joint = OEM spec?

For me, aftermarket is more about trial and error than accepting claims that they are made to OEM specs. It's a rare manufacturer that breaks down their products, materials and construction vs. OEM. Heck, Bosch claims they are made to OE specs and yet they don't work as well, or consistently. So there's one manufacturer that builds to OE spec but the product doesn't perform to OE spec. I believe there's more to creating a quality product than following OE specs.

I take you word that Autolites have worked well for you but for me, when making a purchasing decision, made to "exact OE specs" is a far less valuable statement.

 

[Zach]

I pretty much run OE parts for the most part. Not because I have easy access to them, but made specifically for my 2. There is a lot of aftermarket junk out there with a lifetime warranty, but how many times do you want to replace it? Plugs? Spend the few extra bucks and get delco plugs. No brainer. Only thing I'm running non OE is my headers, plug wires, heat issue, tie rods, OE suck and half shafts. Had two OE spares but they went to Australia. And 600 a piece, I'll snap the cheap ones. Just my .02 for what it's worth

 

[Best4x4]

Bosch plugs are poorly designed. The tip of the electrode is flush with the insulator. They foul extremely easy and I know from experience (tried a set back in the day, and they fouled up with less than 3k. Had plenty of CEL's due to misfire faults). Those plugs are massive waste of $$.

OEM Specs on a spark plug comes down to the size of the plug, plug depth (how far it goes down into the cylinder), heat range, and threaded or stud head design. The only place different companies really tweak their plugs is usually the tips. Willing to bet the AC Delco's are just rebadged NGK's since they're made in Japan.

I have no problem with non OEM stuff. I DO NOT buy the cheap aftermarket no name stuff. I stick with well known and proven parts like Autolite, Champion, NGK, Gates, Stant, K&N, Diehard, Optima, BFG, Goodyear (OEM Bridgestone's were a joke btw), BWD, Dorman, Cardone, Mobil1, Royal Purple, G2, Bilstein, Holley, MSD, or Magnaflow just to name a few.

Guess when my wife's H3 is due for a new front diff bushing I should stick with the OEM one huh? It's OEM design will keep you coming back to the dealer for sure..... Just saying.... OEM is great for some stuff, but not everything.

 

[alrock]

I think you missed my point. "OEM specs" does not guarantee a great product, which is an implication you made earlier. How would a customer know that Bosch products "are poorly designed" when, at the same time, they meet "OE specs"? Also, I never stated that OEM products were superior, though you implied that I made that statement.

What I've attempted to state is that the best test of aftermarket products is customer usage and testimonials, not the claims of the manufacturer. A customer should look beyond the words "exact OEM specs" or the like when making decisions on aftermarket parts or they might end up with inferior products as evidenced by Bosch and EMPI, whose axles snap like twigs.

 

[Best4x4]

I'm sure the Bosch plug does meet OEM Specs like the thread, heat range, plug depth, and material (hence platinum, iriduim, or copper) per application, but like I said Bosch then re-invented the wheel with their electrode tip design. Where other companies like Autolite, NGK, Champion, and Denso just made it to the same specs and slapped their part # on it and moved on.

Autolite, Champion, Denso, and NGK all match the AC Delco design so unless you get the wrong plug I doubt you'll ever see a difference.

That's all I'm trying to point out here. Maybe we need to compile a list of working non OEM parts. For future reference, listing what works well and what doesn't (like Bosch x2/x4 plugs) for example.

I've just noticed most post on here always refer to OEM Parts as the #1 choice and that isn't honestly the best part out there for every single application or we'd all be in bone stock H3's.