New car mileage

We rented a new Chevy Malibu a couple weeks ago on vacation. We averaged 31.2mpg over the 450 miles we put on it. I'd say 60% of that was highway, which 1/2 of was stop and go rush hour highway traffic.

The Malibu is definately not as nice as they used to be, cheaper overall feel, radio didn't sound very good, controls not that intuitive, somewhat underpowered when trying to merge onto the highway....
In my opinion, the 4 cylinder engine that's in the newer Malibu's is to small for the size of the car, this making it under powered and poor fuel mileage. The 2023 Colorado's are all going to have a 2.7 4 banger, that power plant is way to small for the Colorado. GM is making the truck bigger and putting a toy motor in it. The inline 5 was a good engine, was good on gas had plenty of power and would run forever, this is why gm quit building it and the 3.1 V/6 as well.