2007 Silver FJ ~130k
As a follow up to my post about installing irridiums in my '07 FJ on 11/13/20 at 120k, I now have 133k on the vehicle and have definitely noticed a drop of about 2 mpg over that time period. Don't really know why. I think all the other maintenance and variables remained the same. The irridiums look consistent but perhaps too rich. What do the members think? I replaced them with the correct OEM copper plugs. I will monitor MPG and update this post.