I finally bit the bullet and changed out my plugs this afternoon. Truck has been idling like crap recently, and my mpg's seems to have dropped over the past 10K or so
68K on the truck, all 8 plugs came out with no issues.
As with beechkid, I got a set of SP515's for $8/pc from O'Reillys and ran 2 20oz bottles of Techron for about 40gal of fuel earlier this week it to hopefully clean out everything as much as possible.
Got some AeroKroil from Kano directly. 2 cans for $12 shipped--Best deal around.
Offer code - LATE
Kroil works... I stopped twisting the plugs as soon as I started feeling more resistance than " wrist tight" and let it soak more and tried again 15-20min later. Repeat. 5 of 8 gave a bone chilling creak all the way out, but they weren't more than "wrist tight" so I kept going until they came out. The 2 rear plugs closest to the firewall were tighter than others; when I first cracked them open with 1/8 turn, I let those soak longer. After taking a 2hr lunch break with the wife, the last 2 came out fairly painlessly.
It took a bit of self-control from getting overly confident to remove the others after the first one came out.
At 68K, the tip of the old plugs looked worn, and the gap looks like it's grown from wear on the ground as well. 2 of the plugs had some carbon crud built up on the shank. That must the the stuff that welds the 2nd half of the plug in the hole and causing plugs to break. It's not clear to me how these plugs would have lasted until 100K
In all, I think I spent a better of 5hrs on-and-off, including a lunch break.
Will take the truck for a spin later tonight to try things out...
My ego is a bit inflated at the moment and I'm busily patting myself on the back
In hindsight, I've always used top-tier gas, so I don't know if that helped. Didn't see too much carbon buildup on 6 of the 8 plugs otherwise.