I put in these TR55s about 2 weeks ago and wanted to pull one to see how they looked. I have had a wait4me tune the entire time these plugs have been run and have not run any cleaners through my fuel system in the time period either.

From what I see they look ok but have some black around the top of the threads. Does that mean the truck is running rich?

Here is a few pics, sorry for the quality.

 

Looks normal to me

 

doesn't look bad to me either, but some pictures in focus would help.

 

Yeah I just cant get in close with this POS camera I have. The plug tip looks good the only part that looks different than when they were new is that black on the upper threads of the plug. Just didn't know if that shiat was bad.

 

umm...my plugs looked brand new after 40k miles.
I was doing my headers on a member's lift and he asked me how many miles I had on the plugs

"umm, about 40"
"40 or 40,000?"
"40,000, why?"
he showed me a plug he popped out

 

You don't judge a plug by the color of the threads. Look at the white insulator on the center electrode to judge your plugs.

 

So I guess they are good then.

Is this a good way to tell if my tune is doing the right thing? Im so worried that Im running to lean or rich.

 

If you have crusty black spots, that's carbon buildup. You most likely need to run through a combustion chamber cleaner, such as Seafoam or something similar.

Medium brown to light tan is perfect color.
Black is pig rich.
Black and crusty is burning oil.
White to very light brown is lean.
White and crusty is coolant leaking into the cylinder.

I disagree Yogi, I never use the white ceramic to read the plugs, it's always the center electrode and grounding tip that I look at. Been reading plugs closely on race snowmobiles all of my life...

 

I did a little more research on this. Looks like we are both right. Check out the Autolite website pics. Note the comments under the "Appearance" section.

 

I wouldn't run seafoam. I would fix the tune though.