Gregg

I unknowingly road tested Bosch platinum +4 spark plugs P/N 4418 in my 3.4L 5VZ NA 2001 Dcab Taco for 35,000 miles. I recently read a lot of topics in YotaTech about concerns with Bosch platinum plugs due to the Taco "waste something" ignition system where the right bank of plugs directly under the coils have different style of ignition than the left bank of plugs that have high volt wire going to them. When I removed the plugs to inspect them, I was surprised to see Bosch +4's, and I was surprised to see considerable wear on the LT side but perfect condition on the RT 3 plugs.
The attached pics show a typical plug from the RT bank of 3 plugs. These have a normal round fine wire electrode. The other pic shows a typical plug from the LT bank of 3 plugs. These have considerable wear on the center electrode. The wear has gone from round down to a star shaped (6 sided?).
I did not notice any performance issues with these plugs.
I tow and haul w/ my A/T Yota. I live in MN where this winter was down to -20F. No starting issues. No issues towing on I-70 thru CO mtn passes.
I post this as FYI incase it's helpful to someone else.
Sorry about my photography. It's hard to get close up pics in focus.