Opinions on used spark plugs

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I finally changed the spark plugs in my Dodge. I have no idea of the mileage on these. At least 65-70K because that's how long I've owned the truck. Still ran great on the old sparkplugs and runs the same on the new ones. Replaced with NGK V Power. Also replaced the wires, cap and rotor. What's you guys opinion on the old ones??
 
Those are worn out. Conventional plugs should have a sharp edge on the center electrode.
 
Valve cover gasket leaking on one side? The first one looks off a bit, check the wire to that plug and the terminal inside the cap.
 
Those are Autolite Platinums. That's why the center electrode is shaped the way it is. Cylinders look to be firing very clean.
 
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The gap on these were not that bad. I didn't actually gap the old ones but compared to the correct gap on the new ones they looked reasonably close. I think the spec was supposed to be .040.
 
IMO, good preventative maintenance, and you were able to do it yourself - good for you!
You could not have known their condition otherwise.
What time s the total mileage on the vehicle?
Many years ago, I had 2 issues ( different cars, small-block Chevy, and VW Rabbit) in which the internal resistor messed up somehow. Plugs were not that old as I recall, but combustion side turned black from occasional missing. I could read greatly different resistance on the bad ones. Changed the plugs and restored perfect operation. Years later, changed those plugs and they were all perfect light brown.
Similar experience on common Briggs & Stratton lawnmower - changing last year’s perfect-looking plug with correct gap changes a non-start into first-time start. One variable!
 
Inside part : Look pretty clean, gap seems fairly consistent
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Outside part : not so good
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I don't often see rusty plugs on the outside like that...well all my car have their plugs hidden under one million stuff, that could explain !

Well, if they had 65-70K, I still think you did good changing them (especially since you did it yourself), just to prevent some later removing issues, if the rust had gone worse.
 
The two plugs that have some oil/residue on them -- where they the back two on either side closest to the cab of the truck? Asking that because, I changed the plugs on my neighbors truck -- 2000 Dodge Ram 5.2L -- and his back two plugs on opposite sides looked like yours. I replaced with OEM Champion Coppers.
 
In aviation, Sparks plugs are never changed until needed.

Those don’t look bad at all.

I think a lot of plugs get tossed for no really good reason.
 
I assume in the photos they are 1-6 left to right and top to bottom.
So which ones had oil deposits?
Looks more like a penetrant was shot on before removal.

I agree with Popsy on the rust. Preventative maintenance is rarely a wasted effort.
I also agree with Linctex in that many a plug is replaced too soon.
My car's plugs were 10K overdue when I got it. Of course there was no change in operation. No sweat there.
It gave me a chance to look things over--just like looking around during an oil change. Get off on the view!

Also, someone could've installed cheap/incorrect ones. This goes for any vehicle.

A friend had an S-10. We changed plugs only a bit early. There was an improvement so that was good.
 
One cyl looks to have higher than average deposits possibly a valve/seal guide worn passing oil into CC. Of the Plug in that one was way out of index. causing a higher misfire rate.

Nothing Horrendous.

That gap looks WAY bigger than 1.1MM more at 0.07"
 
Indexing usually isn't an issue and it looks to be running a bit richer than the others not oil fouled. Having cap and wires it could be from a terminal or cable causing a slightly higher misfire count (not high enough to set a CEL) or an injector causing a bit of trouble. Checking the wire Ohms and cleaning the terminal cost nothing.

These engines use a Deka injector that are known to have some issues at this age, not a lot but more than I usually see. The ones with issues I see usually have a very slight drip, like one drop every 5-10 seconds.
They are not repairable and should be replace once the issue is confirmed.
 
My opinion is that the car is running well according to the look of the plugs....but I would have changed them and probably used the same model plug.
 
You did good. I like and install a lot of Autolite plugs. It's been my experience that the Autolite Platinum plugs (the one's you changed out) are good for 70k mile on average. So you were on time based on my experiences. The Autolite Double Platinum plug will go 100k while I have seen Autolite XP Iridium plugs go 140k miles and still be in spec gap wise.
 
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I'll stick with the oil ash deposits. Sure it could have higher than normal misfire count caused by randomly poor indexing >or< poor inj spray pattern, or flash over since that plug was oil soaked on the OUTSIDE. I don't recall saying anything about oil fouling though the ash residue can cause fouling or high misfire count. At least This cyl wasn't DEAD.

I was a mechanic over 40 years ago. Just working on old memories and shade experience tree on my own stuff 20 years ago.
 
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