Newbie here, so please go easy on me.

I have a 2007 Civic Hybrid. I purchased the car new.

For the first 30000 miles I averaged 50mpg with a best of 59mpg for one tank (over 610miles on a tank of gas!)

The factory tires wore out so I had them replaced with a set of Pirelli's, and had the alignment checked. My fuel mileage then dropped from easily getting 50mpg to barely getting 44mpg with aggressive hypermile driving. I assumed it was the crappy Pirelli's so I had them replaced with Michelin Primacy MXV4's. The mileage is better but still way off for this time of year at 47mpg.

It seems like the batteries have lost their "punch". I used to be able to "glide" on the electric very easily with the mpg gauge maxed at 100, now if I just touch the throttle the mpg gauge drops below 40.

Anyone have a similar experience? Or can anyone give me a direction to point the dealer?

I have an appointment for the local dealer to look at it tonight.