I have a '03 QC 2wd 4.7L, 118,000 miles.
I know this topic has been beaten over the head soo many times, soo I am sorry in advance :/. I have already read about 10+ posts about this. The only reason I am asking is cuz I haven't seen anymore that has put iridium spark plugs in their engine?!?

I have purchase the Autolite XP5224 Iridium plugs, but have not installed them yet. I currently had the Champion 7318 Double Platinum plugs for a little over 2 years. I haven't noticed any performance problems but I am not really sure what to look and/or listen for?!? I have been reading a lot that most people use the OEM Champion 439 and/or Autolite 5224 plugs.

For some reason I was not able to find the Champion 3923 plugs which everyone is talking about...

Soo I am wondering if their was a specific reason as to why nobody uses the iridium plugs, do they not give your the most performance/fuel economy??? I know they are not the OEM plugs.....

Also, recently a kind of ping has started to occur on the passenger side by the headers I think, so I don't know if has to do with the double platinum plugs I am using or maybe another problem?!?

 

NGK, normal, stocker replacement. Work fine. Arguable about gains.

As for syptoms, some are prevalant, knocking, pinging, etc...but I just do them at regular intervals to ensure they arent the culprit for any issues.

 

First off you are looking for the wrong plug its autolite 3923. As far as plugs getting you better performance and mpg you might notice a very small increase. Which you will notice a big increase if your plugs have about 100k on them but other than that its not worth spending 5.00 more per plug. Pretty much everyone on here agrees with using oem or autolite 3923 almost everything else makes the truck run worse. I put 3923's in my truck and they love them no problems with them at all.

 

All those fancy sparkplugs are a gimmick to get you to fork over more $$$$ That’s it.

 

I know I am gonna catch flack for this but frankly I dont care. I'm trying e3 plugs and have seen almost 30 miles on the tank increase. That and with a 100k mile refund warrenty why not try them.

 

That's ok I have used others before but usually go back to basic plugs.

So you like the e3 plugs I was using Bosch platinum but they craped out rather early on me so back to basic plugs.

I do think most fancy plugs dont do much or anything for you its all in the head my opinion.

 

same driving route to and from work every day on the highway, and running several tanks through never less than 30 more miles to the tank than before I switched my plugs.

 

Futbolplayer

If you have the money to spend just do it then get back to us on the results.

Lebbie54

Ok well good if it works keep using them if it saves you a tank of gas at $50 a tank thats great savings.

 

Not sure what you read but I read it gave him 30 more miles to the tank. $50 a tank? holy F man it just cost me $70 to fill up a couple days ago. I agree with using basic champion copper core plugs gapped to .040, the only thing I will fork out extra for are headlights.

 

Ha Ha ok MoparMan1991 I dont belive in the fancy plugs also but do try one every now and again for the hell of it.