[Andyman]

The best mileage I ever got with an automatic transmission was in a 1994 Saab 9000 Turbo. I took a highway trip of about 100 miles and reset the trip computer at the beginning. I drove 45 to 60 MPH most of the time, but there were also a few stops. At the end of the trip, the car's computer said that the average MPG was 43. This is better than the Saab 900 which usually can't get more than 33 MPG. The 9000 probably has a higher gear in the transmission. If the speed goes below 45 MPH, the car shifts down to third and the fuel economy goes down. For low speed driving, something with a smaller engine should be more efficient. The Saab 9000 has a 2.3 liter engine.

I remember reading in Consumer Reports that a Saturn SL with automatic transmission achieved 50 MPG in their highway test. Old Toyota Camrys before 1992 got about 46 MPG in the Consumer Reports highway mileage test.