spark plugs at 75000 miles.

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Left Coast Geek

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So after reading about high mileage spark plugs causing a decrease in mileage, and wondering why I wasn't seeing the sorts of gas mileage others report, I figured 75000 miles wasn't too soon to put in new plugs, just got 6 NGK Ruthenium HX installed.

These are the plugs that were pulled...

PXL_20240620_220215565-X4.jpg

PXL_20240620_220301788-X4.jpg

all gaps were a little too tight for my 0.030" gauge and way loose on the 0.025... I thought they are supposed to be gapped 0.032 ?

anyways, I'd say that for 75000 miles, these plugs look pretty good.

edit: ok, Ford says gen2 uses 0.028 gap. hmmm, NGK says their ruthenium plugs come gapped 0.031" (0.8mm)
 
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SyndicateZ

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So after reading about high mileage spark plugs causing a decrease in mileage, and wondering why I wasn't seeing the sorts of gas mileage others report, I figured 75000 miles wasn't too soon to put in new plugs, just got 6 NGK Ruthenium HX installed.

These are the plugs that were pulled...

View attachment 81382

View attachment 81383

all gaps were a little too tight for my 0.030" gauge and way loose on the 0.025... I thought they are supposed to be gapped 0.032 ?

anyways, I'd say that for 75000 miles, these plugs look pretty good.
What type of gas milage u getting?
 
OP
OP
Left Coast Geek

Left Coast Geek

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kind of all over the place, but mostly 13-17 when not towing, 12-13 when towing a fairly streamlined 4500 lb trailer at a steady 60-65 MPH.
 

BigOleFordFan

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What old gearhead said. No more than 60K with the turbos. TONS of threads on the plugs.
Ok, so what exactly does the number of threads have to do with whether or not the plugs need to be replaced ?

In 50+ years of driving & maintaining my vehicles, I have yet to see any threads suddenly (or not so) disappear...although I have known some folks who messed them up by over-tightening or cross-threading them, in which case they will get damaged but are still in the same place they always were just not in great condition...

Just hoping someone can enlighten me on this, cause everything I've ever read & seen about plugs (in any vehicle) says that if they look like the ones the OP showed (which normally occurs between 60 & 75K miles), they should be replaced asap :D
 

BSarchet

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Ok, so what exactly does the number of threads have to do with whether or not the plugs need to be replaced ?

In 50+ years of driving & maintaining my vehicles, I have yet to see any threads suddenly (or not so) disappear...although I have known some folks who messed them up by over-tightening or cross-threading them, in which case they will get damaged but are still in the same place they always were just not in great condition...

Just hoping someone can enlighten me on this, cause everything I've ever read & seen about plugs (in any vehicle) says that if they look like the ones the OP showed (which normally occurs between 60 & 75K miles), they should be replaced asap :D
By “threads” he’s referring to the number of different discussions on this forum regarding spark plugs.
 

lv2drive

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Ok, so what exactly does the number of threads have to do with whether or not the plugs need to be replaced ?

In 50+ years of driving & maintaining my vehicles, I have yet to see any threads suddenly (or not so) disappear...although I have known some folks who messed them up by over-tightening or cross-threading them, in which case they will get damaged but are still in the same place they always were just not in great condition...

Just hoping someone can enlighten me on this, cause everything I've ever read & seen about plugs (in any vehicle) says that if they look like the ones the OP showed (which normally occurs between 60 & 75K miles), they should be replaced asap :D

oh man this is so great - thread of the week (no pun intended)
 
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