I use Lucas Oil brand fuel system cleaner. It is the only one that I have noticed actually making a difference in the performance of my engine. Mileage does drop negligibly while it is in your tank, however after your next fill-up you should notice a slight increase in mileage.
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2003 Renegade 4X4 5-Speed, Bright Silver *TRADED for 2013 Wrangler*
PIAA 520 Auxiliary Lights
Garmin GPSMAP 76S
DynoMax Ultra Flow SS Muffler
Amsoil Ea "Absolute Efficiency" Air FilterNokian Vatiiva 235/70/R16 Tires
Pixeldzn's "RENEGADE" decals
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