I changed mine at 65,500, all came out fine, tips looked good as new. The new plugs made no difference in the way it ran or mileage.

 

Mine were changed with the whipple around 50k, we did another truck at 65k, and another truck at about 65k too. Never had one break yet.

 

To the OP:

The only nightmares have been with the 3V engines. The 2V plugs actually have a tendency to loosen and blow out by themselves, not stick and break like the 3V.

 

In 2001, I took the original plugs out of a '76 F250 running a 390. Granted the truck's mileage was only 79K (farm truck) I can tell you it probably had 4x's the hours a truck with that mileage. A complete tune up didn't give the boost that rebuilding the carb did.

 

i have the "if it's not broke don't fix it attitude" also....unless your gas mileage goes down tremendously. My 98 4.6 started to skip a little at 190,000....i pulled the plugs and realized they had never been changed! I bought the truck with 150,000 miles on it so assumed they had been changed. the gap was right at .8....truck ran fine except a light skip every once in a while...i think you will be fine until you notice skipping, gas mileage drop off, or rough idling and loss of power

 

I'll send you the Special Modified plugs I bought that I may not use

 

So far, I am winning. There is a guy who THINKS his had not been changed, and he bought it at 150k and changed them at 190k. He should be disqualified because he DID NOT put all 190k on them...

 

My previous truck had 108k on it when I bought it and I didnt get around to changing the plugs/wires on it till probably 120K.

Plugs really werent in that bad of shape. Probably could have gone longer if you really wanted too.

Freind of mine just changed the plugs in his 97 Blazer....180K on the stock AC Delcos and they looked great

 

I think you guys are all full of it

 

'Nother buddy of mine had 230ish K on his old 4six and I question the amount of times the plugs might have been changed on that. I would think at least once, who knows though.

I plan to pull mine on my 06 sometime soon, has 37K on it. Mainly because I am scared that if I go any longer without pulling them I will end up not being able to ever get them out.
Oughta do it on the 97 sixer too, only has 32K on it.

 

I've still got the original plugs in my wifes 2000 Expedition, purchased in August, 1999. Still has the original air cleaner and the original fuel filter. It would have the original air in the tires, but they were changed with the Firestone recall.

Of course, it only has 8,800 miles on it.

 

Wait a minute! I might just take over the lead here. I have a 1986 Honda lawnmower that still has the original plug in it. That means it's been in the engine now 22 years going on 23 and it gets used every year. It still passes the Sarah Johnson test- it starts every time the first time. Does that count?

 

Yeah, but how many miles are on it??

 

jbrew your a jack *** the plugs in the 2000 and up ford cars (dont know about other cars) have plugs that are made to go to 100k ive had people come in to the shop with 120k to change them and ive pulled them out to see they were still fine. and to answer your question the plugs are a little bit of a pain in the *** to take out. go buy pb blaster and soak the plugs befor you pull them for about 20 mins then just be carefull when pulling to not crack the ceramic out of the metal

 

Jack a$$ huh Your post shows how much you don't know and/or is totally irrelevant.

For one thing, you don't need PB Blaster removing plugs from 4 thread heads. Another thing, this is a truck forum, not a car forum. My statements are for such.

I have already stated 3 or 4 posts down these plugs are rated for 100k , but gave my opinion on when I believe they begin to ware.

These plugs DO NOT have a problem with breakage from 97 - 03 4 threads and improved present model 2 valves heads. The category the OP falls into IS the 4 thread heads.

If anyone is a jack a$$ here - It's U Mister.