Knock, ping or rattle is still usually the result of a batch of bad gas and could include some water. It may take one to two tanks to clear it out. The techron should do it with one tank. I would stick with the 87 octane like the car is designed for. Try using a different brand of gas like Shell or Chevron to clear up your problem.

Your TCH has individual knock sensors to retard any one (spark coil) cylinder that has a ping. It sounds like it's at full retard and the combustion being to low, allows some pinging. You might have carbon buildup on your pistons, but I doubt that can happen with today's no-lead gasoline's. If they are any valve or piston deposits the techron should clear that up. A good way to speed cleaning the engine is to drive it on the highway around 70 mph for a 50 to 100 mile loop.

for ukrkoz:
What I learned about the 3.0 Ranger V6 engine. Your ping in that engine is a design problem. Especially if it's the FFV (flex-fuel vehicle) engine. My wife tried various gas additives and has had some result. She hit the nail on the head once she started mixing 5 gallons of mid-grade with 5 gallons of 87 octane in her tank. After a while she started filling at half tank once then would use the mid-grade at the next fill with 87 octane. it sure lit up that old sluggish 3.0 and what new power it had in low and second gear even though it was a automatic. It sure got rid of any pinging in that Ford engine.

I read in google a few years ago many Ford dealers service dept. suggested replacing all 6 of the fuel-injectors with new ones. It helped very little, but most still had the same knocking problems when accelerating or going up a hill. I'm sure glad I had read that, I was about to buy a set and install them myself. My wife bought a 2010 Ranger and has the new 145 hp 4-cyl engine compared to the older 147 hp V6. She now gets 4 mpg better mileage (all aluminum engine) and no pinging at all. She also uses the phillips 66, 87 octane gas. Ford has done well with their new engine design, but I like Toyota's design best.