Bass Cat Boats wrote: That would be correct, and the other tank should be your oil reservoir. BCB Actually the guages have setup for two tanks AND an oil tank. Since it has two tanks switched thru the BCB board I just set it up for one tank. I think the differences on the oil tank may be a poor sender. I filled the oil tank all the way up and it reads 2.9 gallons. At 2 gallons it read 1, and at 1 it read empty. I have run one fuel tank out. If I have time I think Ill try and go through the regular calibration sometime this week for the fuel tanks instead of the default. The default is way off for either tank.–Bob La Londe Forums, Free Lures, Product Reviewswww.YumaBassMan.com CNC Molds N Stuffwww.CNCMOLDS.com