I just don't see how the new estimates are supposed to be more accurate. Every vehicle I have owned has shown mileage equal or better than the claimed mileage, and I drive hard compared to 99% of the people on the road.
My 2001 Trans Am six speed was rated at 19/28, now it is rated at 17/25. I have kept an Excel spreadsheet since I bought the car new in 2001 which I tracked the fuel economy since day 1. This cars will see 31mpg strictly highway driving with an average speed of 80mph.
I drive 24 miles round trip to work and home with 12 stops, and speeds ranging from 30 mph - 60 mph. When I accelerate from a stop, I usually will be about 10 car lengths ahead of the other cars around me by the time I reach speed. Most people take forever to get to speed. Driving like this, I usually average 19-20mpg. I tried a few experiments where I accelerated as slow as everyone else and I averaged 24mpg.This is without the skip shift 1st to 4th feature. I use every gear.
I only saw 17 mpg one time and that was when I made a lot of runs at the race track.
My 1985 Corvette Auto was rated at 16/23 and is now rated at 15/21. This car can see 24mpg with only highway driving and back and forth to work I see 18mpg with the way I drive. I have not experimented driving slow like most other people.
(I now have a new engine with AFR heads, a large cam and a 3200rpm torque converter so my mileage has dropped to 22 on the highway and 17 back and forth to work.)
My 1987 Suburban 4x4 was rated at 13/16 and is now rated at 11/15. This truck has seen 16mpg on the highway. I do not drive it to work but overall it averages 12-13 mpg.
I had a 1989 Celebrity 2.8 that was rated at 23/30 and is now 21/28. I say 30mpg highway and 24mpg to work and home.
I had a 1991 Honda Civic CRX 1.6 that was rated at 28/33 and is now 24/30. When I drove this car to work, I accelerated at full throttle almost every time. (That is what it took for acceptable acceleration in this car) I still averaged 30mpg. I never got any highway estimates on this car but it would surely be a LOT better than 30mpg.
I had more cars but did not keep accurate mileage for them except for my 83 3/4 pickup, but there are no official numbers to compare it to.
