[dannylightning]

well its going to weigh less than a passenger, i highly doubt you will see any mileage difference from adding a few extra lbs to the trunk.. that air pump instead of a tire is pretty ridiculous if you ask me.. i have been thinking about doing the same thing..

 

[Clump]

Here's a link to a thread in the how to section where Obermd did it - http://www.cruzetalk.com/forum/57-how-forum/9312-how-install-gm-specd-spare-tire-eco-mt-trunk.html

He doesn't mention any change in gas mileage. The change was pricey - $550, but he used all new GM parts.

 

[obermd]

In city driving, the extra weight might reduce your mpg slightly. No change that I can detect on the highway. Also, the car drives the same.

 

[AkotaHsky]

I dont think the difference is that big. I did a trip to Atlanta from Central Florida last year with my Cruze ECO with K&N Intake, as I did not have the tune yet. I got 45-50MPG most of the way, thats with 2 people and the car loaded down with gear and a cooler full of booze and stuff. Was atleast an additional 200lbs in the car from the stuff.