Dark sticky gunk on spark plug threads

Hey I'm somewhat new to posting on the forum as most of the information I've needed has already been posted. I have a V6 4.0 TRD off-road 2009 that I bought a year ago used with 27,xxx miles, I've been tackling all the 30k maintenance this year myself learning as I go. I just replaced the spark plugs yesterday at 48500 miles for the first time (late I know.) it went smoothly but all 6 plugs have a film of dark tacky gunk over most of the threads. The ignition part of the plugs look great as far as I can tell (I'm new to this) they are dry and uniformly grey. The driver side plug closest to the firewall (NGK) seemed the least affected. With such low miles on the truck I would like to think this isn't a problem since it's just the threads maybe it's residue from some sort of anti-seize compound they used in the factory? Maybe it's a result of simply changing them late? Hopefully it's not an oil problem.

I am inclined to drive a while and pull them and check them again. The truck was running fine before the change and continues to do so.

Any experience with what this is?

 

Its likely a factory anti-seize

 

real question... Does it run better?

 

That is what 6 burnt out spark plugs look like.

 

I'm at 31k and even more inclined to change mine very soon, lol.

 

Bottom line the spark plug police are not going to come and get you the only problem would be emissions testing and that is why Toyota says to replace them at 30K and it could affect your emission warranty if you had a problem. Drivability, protecting your converters and fuel consumption plays into this too.

 

Well that's a relief. Yeah it seems to have a bit more pep on acceleration now but that might be placebo. Not a huge difference in starting or running.
Another thought I had was that although the manual says for oil/ filter change it takes 5.5 qts, I've noticed that when checking the engine cold the oil level is a bit high- over the top hole in the dipstick. I've read about that on the forum and people were either adjusting to just 5 qts or so or just ignoring it and calling it fine/ within tolerance. But I wondered if maybe that amount more oil could have caused some leakage into the threads? it sounds like I'm fine though and it was probably anti-seize/ old plugs. In any case it's easy enough to check them I think I will after a few thousand miles just to see, and maybe go down to 5 or 5.25 qts oil change too.

Thanks guys this forum is super helpful for people like me trying to learn about their trucks!

 

More oil is not going to cause any leakage of oil on the spark plug threads.

I would put in whatever oil amount called for in the manual and call it good.

You are way over thinking this.

 

The gook around the plugs is normal every pent roof engine or hemi ever made did that so is oil around the plugs no panic required.

 

My plugs looked exactly the same when I swapped them at 30k. Normal.

I have found that 5 qts + 10 oz seems to be the ideal fill amount for my motor when I do my own oil.

 

Oil leaks into the spark plug wells have been happening for decades I'm old enough to have worked on old Dodge Hemi's they used to fill up with oil right over the tops of the plugs (oil is not conductive so you would never know) Honda's would do the same thing it is the design of the engine the 4 liter is the same type of design. If only one drop of oil leaks in over 3 months think of the possibilities after 30,000 miles. Crank case level has nothing to do with it unless it's empty then it won't leak.

 

If you don't have an owners manual, you can download it for free at this site:

http://www.justgivemethedamnmanual.com

Oil capacities for '09 6 cyl on page 483.

Also available at toyota.com - the one above is accessed easier/faster

 

My original plugs had none of that on the threads. Look at the burn ring on the porcelain - mine were no where near that dark - I changed them at my 3 year Spring service / 24,200 km. I put anti-sieze on the new plugs so we'll see if they look like that at my 6 year Spring service.

On another note, I add a 4.4 liter jug when I do my oil and filter change - start - adjust to full mark after an hour or so (while I continue on other service items). It takes between 4.8 and 5 liters total.