DIY Spark Plugs Replacement on 2015 PreRunner

I followed this guide and this guy's video to change my spark plugs. My PreRunner was already close to 96,000 miles, and wasn't sure if the previous owner changed the plugs on the recommended intervals, so I did it then.

For me it was pretty straightforward. Since it was my first time, I took my time exploring and even tried to change the PCV valve while under there (but ordered the wrong kind). My Dad and I took about 2.5 hours doing it all in the end.

I kind of left my plugs gapped at 0.036 for now since I wasn't too confident with using AutoZone's coin shaped gapper (turns out you can just by pressing it, if only I thought of that).

Turns out it's a good thing I change the plugs when I did, because the old ones looked and smelled burned with pretty large gaps.



New ones by Denso:



What helped make the process a bit faster and efficient was using a flexible socket extension and a 6" magnetic spark plug socket tool.

 

Also, need to figure out if my engine is in good shape. Couldn't help but notice that maybe I have burned carbon on the end threads near the spark?

 

Those plugs look pretty normal to me, but others may see something else.

I am pretty sure, when the truck left the factory, there were 3 plugs from one manufacturer and 3 plugs from another. Apparently done to keep 2 suppliers happy.

So if you see two different brands of plugs in the plugs you took out, then the plugs were never changed.

 

When I picked up my 06' a couple years ago, it had 220k on it. No CEL but I could feel a slight misfire. So I changed the plugs and turns out they were original. Needless to say, they were whooped!

 

I'll double check again. My dad who helped hold my tools and grease the plugs was happy to throw away the old plugs... But trash doesn't go out until tonight. I'll dig it back up and take a closer look.

I was afraid of the engine burning possibly burning oil. I'll take more pictures once I'm able to.

 

Goddam!

 

At my age and if I keep mine which I have no intentions of selling right now my current plugs may outlast me.

 

Just check the oil every couple weeks and you'll see..

 

Here there are. Apparently they haven't been changed at all - these were the original spark plugs from factory as it seems (2 sets of plugs).
The dark stuff seems to either be burnt oil or carbon build up, not completely sure :

Passenger side plugs:

Driver side plugs:

 

They look fine to me, just a huge gap

Internal combustion is a dirty business, don't overthink the appearance

 

Copy

 

.036 is fine. I’d rather have a smaller gap than a larger gap. (But not too small) Plugs are recommended at 30k intervals. I do 50k, because they actually still look good even at 50k.

Good job on the maintenance.