Hello,
I recently purchased a set of NKG iridium plugs for my 3.4L v6 4Runner. However, when I spoke with the dealer to see how much they would be to install, I was told that I could not use them in the 4Runner application. They said that they would be out of spec and run too hot and could damage the engine, and further that I could only use the factory plugs. This surprised me as I know Toyota offers these kind of plugs as standard equipment on some of their other vehicles. Does anyone here have any experience with these?

Thanks in advance.

 

Like the dealer said, stick with the stock plugs.

Oh, and welcome to the boards!

 

If they are the same heat range as the stock plugs they won't make the engine run any hotter or do damage. I've also been running a single ground electrode for ~7k miles now with no ill effects.

For it to be same heat range as stock it has to have a 5 in the 4th position like the following NGK code: NGK BKR5EVX11 and it should end with 11 so it comes pregapped to .044". However, the stock plugs seem to last for 30k miles and they're dirt cheap compared to iridiums so it may not be worth it to make the switch unless you're looking for a >30k mile change interval.

 

The stock Laser Platinums are DIRT Cheap? Where????

Inquiring minds want to know. The Iridiums were the same price as the Laser Platinums as far as I could tell...

Dr. Z

 

The dealer (as usual) is full of ˟˟˟˟˟. I run Denso Irridiums with NO problems. I run the 1 step cooler to assist with ping because of the s/c but you can run irridiums.

Paul

 

If you're refering to this "However, the stock plugs seem to last for 30k miles and they're dirt cheap." Go to your dealer and ask for stock plugs for 5vz 4Runner, they'll give you Denso K16TR11, I paid ~1.70 per plug. They are not laser platinums they are stock iso construction.

 

Hey Fatty,

Well, my truck had the dual-electrode Laser Platinums in it when I changed my plugs for the first time. I was under the impression that they were the factory installed items. I do know that NGK and Denso make a copper plug for these trucks, but that the Laser Platinums were recommended and are what came factory installed.

Maybe that's a myth, but I know that a lot of Toyota models come with Platinum plugs from the factory. My Supra did, too.

My .02
Dr. Z

 

Hmm, well maybe the new 4Rs come with Iridium plugs. When you changed your plugs were they all the same? If so they probably were installed later. All of the 5vz that I've heard of came with Denso on one cylinder bank and NGKs on the other. The driver's side bank also shows a lot more wear on the electrode.

 

Yeah, all the plugs were the Laser Platinums. Since I bought my truck used, it's possible that the dealer from whom I purchased it installed them during the Toyota Certified Vehicle inspection/setup of the truck. I put about 25k on them before changing them.

They seemed to have a normal wear pattern to them. I think both banks looked even, but it was so long ago and I wasn't looking for anything specific that I probably wouldn't have noticed unless it was really out of the ordinary.

I don't think the new trucks are using Iridiums from the factory, although it's not out of the question. All the part finders seem to be down right now for the NGK plugs and Denso does not have a listing for the 2003 4Runners...

Dr. Z

 

Great Info! Thank you all for the help. And the warm welcome! Those codes and explanation that Fatty Gave will really help. Once I get them, I'll check their compatability. Sounds like the Toyota dealer is afraid someone will stick in the wrong plug. You'd think that they would just say "make sure that the heat range is 5 and the gap is .044"--But I guess that would be too easy. I hope this thread will help other neophites like myself to sort through the disinformation. I had a hard time locating info on this issue on-line.

I think I'll try to use the NKG iridium IX plugs as what I've read about them is pretty nice: They shouldn't need to be replaced for 80K miles; Also from what I understand they are supposed to do a better job with combustion than stock--Yielding more HP. (Though this is rhetoric for spark plug maketing) I got them for 54.00 so while it is true the stock plugs are 1/10th the price, 10 X "Dirt Cheep"="Pretty Cheep" still.

THX Again

 

I think the Land Cruiser uses Iridium--Not sure but got that impression from service descriptions available on-line....

 

If I can borrow a camera and find my old plugs I'll post pictures of the original plugs after 65k. It's quite remarkable how good they look for that mileage.

 

Sorry to spam my own thread, but I remembered seeing that the new Iron V-8 (the really big one) on the 2003 4Runners use them too.

 

 

Here's some Info for anyone who is not familiar with the different materials:

Iridium Spark PlugDenso Iridium Power Spark Plug— It is no secret that Iridium is 6X harder then Platinum, 8X stronger, and resists melting in temperatures exceeding 4,000 degree Fahrenheit. Denso Iridium spark plugs feature the world's smallest center electrode, measuring 0.4mm in diameter. Because the majority of sparks are exposed to the air/fuel instead of the metal surface, the fuel burn is greater (0.5 increase over platinum), which ultimately improves gas mileage.

 

Here's The contents of a chart I came across for factory configs:
(IR=Iridium, PL=Platinum, STD=Standard)

Avalon-IR
Camry/Solera-PL
Celica-IR
Corolla-IR
Echo-00-IR
Echo-01-STD
Higlander-IR
RAV4-00-PL
RAV4-IR
Seqoia-STD
Sienna-00-PL
Sienna-01-IR
Tacoma-STD
Tundra-STD
4Runner-STD

Think this is from '01.

 

Sucellus, glad to see you made it in!

I told you that you would get a lot of replies. Come here BEFORE you ever go to your dealer from now on.

 

Better late than never, here's that pic I said I'd take of my stock plugs. NGK is on the left and from the passenger side, Denso is on the right and from the drivers side. These plugs were pulled after 65k miles as you can see there is much greater electrode erosion on the drivers side. Otherwise the plugs had very similar insulator colors, one side was lightly coated brown (intake valve side) the other side was uncoated and looked new (exhaust valve)

 

Uh...

What pic?

Dr. Z

 

What you can't see it? Yotatech froze up on me while submitting the reply.