I've installed 5WT Solar trickle charger on my 09 Hyundai Sonata(25-32MPG by fueleconomy.gov). Easy to install. 50$, Just attach to battery.
On my trip to Florida I've got 37MPG. Drove about 75MPH, AC mostly on.
From Florida i drove at night time and MPG was 33MPG(75-80MPH, NO AC).
Regularly getting 32-34MPG on 30%city-70%highway driving.
SO, If you guys want i think it's good thing to try.
*Regular driving(30%city-70%highway) results: 534 miles on 15.6 gallons = 34.2MPG. Just filled my tank today
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