[MeteorGray]

I just changed out a five-year-old, 37,000-mile set of Yokohama Avid tires that came from the factory on my 2015 Mazda3, for a brand-new set of Bridgestone Ecopias.

I was expecting to see a loss of fuel economy based on the widely accepted theory that new tires aren't as fuel-efficient as worn tires, all things else being equal. But I could detect no difference in my first tank's worth of fuel with the new tires, used on a highway trip of 400 miles which had no unusual winds or traffic conditions.

The new tires have deep 10/32" treads on them, compared with the 7/32" treads on the old ones. (BTW, the reason I changed out the Yokos despite the good amount of tread left on them that is that one of the tires suffered a belt separation and tread-bulge. So, I decided that since the other three are the same age and hit the same potholes as the damaged one, I felt maybe it was time.)

Since the fresh Ecopias performed as well as the worn Yokos, maybe this implies the Ecopias are going to be more fuel efficient than the Yokos as they wear in. I'll find out in the miles ahead, unless any enhanced efficiency is too small to discern, given the myriad of conditions one faces on the highway.

In any case, I was pleased to experience no loss in fuel efficiency while breaking-in the new tires.