Before giving my 02' 2wd a tune up, I searched this forum for evidence of successful use of iridium plugs. The only info I found was that our trucks (4.2 litre) do not respond well with many brands other than Motorcraft/Autolite. Many people described how bad the Bosch plugs are and how some brands of platinum don't work. Subsequently I was very hesitant on trying the Iridiums.

I actually went to Napa to buy some of the normal Autolites, (which are identical to the Motorcrafts that come from the factory), and they only had the Extreme Performance Iridiums. They were priced at ~$6.50 per plug and Autolite has a rebate good for $1.50 off each. Obviously I couldn't argue with the price, so I grabbed 6 plugs and chose the Napa branded (Belden) plug wires @ ~$56.00 per set. They wires actually smell insanely bad for some reason, but the build quality is very nice and they have a lifetime warranty.

Now even though my truck only has 54,000 miles, I felt an immediate difference after installing these hogs. The engine is actually less of a thrash machine than when it was brand new. And as far as I am concerned if I can make this piece of crap 4.2 run smoother, i am a happy camper.

If I may say, my truck has never run better than it does right now. I highly recommend the Napa premium wires and the Iridium (xp5144) plugs gaped @ .54. It is NOT worth buying something that is supposed to be ultra high performance that might not work when you can go to your local Napa and for $100 get setup with products that work as well as possible in our engines.


My $.02