Hey, I actually use those tools! When my serpentine belt broke, the 15mm socket was nice to have. And, I think my box van was a little larger than a lifted RAM 1500.
Joking aside, it makes a huge difference. By slowing down to 60 MPH in my 1987 Chevy, I'm pushing 20 MPG- some days I can top it by a little. If I drive at 65-70, the fuel mileage goes down to 15.
Fuel efficiency is just as important as fuel costs, if not more important.
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