On a flight KSEA-KBIL (1hr approx) the tanks were set C=0, L=80%, R=80%. After 45min the R tank was 1160lbs less than the L tank and the gauge was showing a fuel imbalance. Fuel was identical to both engines throughout the flight.Also I can only set the initial fuel levels with all power off. If I try to set the fuel level with the battery and APU on then the left tank always resets to 100% and I get an imbalance.Paul Gardner

Paul have you applied the patch? This use to happen to me prior to PMDG release the update patch.CheersBob

Yes I did a clen install in FS9 and applied the patch.Paul Gardner

Paul, have you gone into the aircraft.cfg and change the number of tanks from 1 to 3? This also helped on my setup. If this does not help, I am going to have to scratch my backside to figure out what else I did to get this to work. :-)CheersBob

"Also I can only set the initial fuel levels with all power off. If I try to set the fuel level with the battery and APU on then the left tank always resets to 100% and I get an imbalance."Not sure if this tip is still applicable, Paul, but did you hit the PAUSE key before you went to top up your tanks?Hope this helps.Cheers.Ian.