I just did a 2 hour trip on the freeway in my 04 GT with an auto and 4.10s. I filled up, got on the freeway, got off two hours later, filled up again. I stayed between 70 and 75 mph.
173.5 miles
7.989 gallons
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Do the math!
I got a set of 4.10's and I love them great HP and the ability to speed up a 50-75% hill inclince and still have enough power/torque to pass a slow car (GUAM BOMB). Living on guam I mostly get about 19-20 mpg, all city, hardly going more then 55 mph for greater then 15-20 minutes. My opinion the best upgrade to my 03GT so far. Also, changing the under pulleys and adding a CAI. Overall distance diffence is abut a 1-2 mpg differance.
I got a set of 4.10's and I love them great HP and the ability to speed up a 50-75% hill inclince and still have enough power/torque to pass a slow car (GUAM BOMB). Living on guam I mostly get about 19-20 mpg, all city, hardly going more then 55 mph for greater then 15-20 minutes. My opinion the best upgrade to my 03GT so far. Also, changing the under pulleys and adding a CAI. Overall distance diffence is abut a 1-2 mpg differance.