I have a 2012 Hybrid EX and I just leaped over the 180K miles mark. My car "knock on wood" is running flawlessly. I purchased this vehicle used 3.5 years ago at 82K miles. I travel about 100 - 150 miles a day for work. I am currently getting about 32 MPG highway miles. I remember getting about 38-40 MPG highway when I first purchased the vehicle years ago. Also (about a year ago) I saw about a 5 MPG decrease instantly when I purchased 4 new tires and a new Crank battery. Don't know if the 2 changes had something to do with it or not or if one or the other has anything to do with it. Should I try to get new hybrid batteries? Would it be worth the difference in gas mileage and efficiency? It's only seen the dealership for factory recalls, all the maintenance is done by a family owned garage. But the advise on battery replacement is unknown. I feel lucky to have the car running so good at 32MGP but if I can make a 10+ MPG improvement by replacing the batteries, should I consider?