Home Forums Gear Hunting Trucks and Four-Wheel Drives spark plug life?

Some years back a friend sold a Ford Aerostar with about 150k. The left rear plug was still the original. To change it, you had to pull the engine. He sold it while it was still working good. Another Ford genius engineer, obviously.

^ ^ ^ ^ ^ or dielectric grease

It's not so much the useful life of the plug
as much as leaving them in for many miles
works slowly towards them seizing up in the
cylinder head, and they often strip the threads
when trying to remove them.
That happens with all makes.

If you're talking the plugs out to check them,
you might as well replace them instead of
putting a used part back in

I had the ones on my 2011 Ram 5.7 changed at 100,000. I thought of doing it myself but after taking a look at what a chore it would be I decided to pay to have it done - 16 plugs plus installation $500 total.
I took a look at the ones that came out and they were a nice tan color and looked like they could have gone another 100,000, but I feel better now. I asked the mechanic about his thoughts on what should be done at 100,000 and he said spark plug and serpentine belt change is about all that most vehicles really need done. In his experience he said that any well maintalned newer vehicle can expect to go 250,000 pretty much trouble free - I certainly hope so because I like this truck better than any vehicle I ever owned.

drover.

As far as putting anti seize products on your plug, refer to the manufacturer first. Iridium plugs aren't the old school plugs that you cranked down into iron heads. Most are made with silver or chrome plating to be used in aluminum heads. Anti seize causes you to over torque the plugs and potentially cause more damage putting them in than you would taking them out. Modern plugs come out just fine at 100K in modern engines. Of course, in older engines with old style plugs, it's probably a good thing.

Been a little over a month since I had the plugs changed. Still using the same wires. No change in the way it runs which has always been good. Gas mileage shows a slight but noticeable improvement. Really noticed it on a 350 mile round trip that had some pretty good inclines coming and going. I've made this trip a couple of times each year for a while. No specifics but this time when I got back there was at least an 1/8th of a tank more gas in the tank than usual.