Fuel Gauge Versus Remaining Diesel Fuel

[PaulR]

Freightliner replied to my email about the same question and indicated 75 to 80 gal was usable but weren't definite about the answer. Understandably so, if they had told me 85 gal and I ran out at 80 I wouldn't be a happy camper. I decided to find out for myself how much usable fuel the tank held. The tank was labeled for 90 gal. I leveled the bus and started pumping out fuel starting with a full tank - fuel almost running out the filler neck. Measured the volume using 15 gal drums at 94 gals. Pumped it from the storage drums through a filter and into a calibrated container. Counted the number of containers (5.546 gal/container) and put back 92 gals. Chalked up the two gals to error when I pumped the fuel out. Also remember reading someone else on this forum reporting their usable volume was 92 gal from a 90 gal tank. My fuel gauge was reading low too until I drained and refilled the tank.

[Mr_D]

But that still doesn't tell you the usable amount. You have to run the fuel level down as you run down the road. You have no way of knowing where the fuel pick up actually ends

[PaulR]

Originally Posted by Mr_D

But that still doesn't tell you the usable amount. You have to run the fuel level down as you run down the road. You have no way of knowing where the fuel pick up actually ends

Sorry, failed to mention I pumped out the fuel through the fuel pickup line. Granted the bus was level and it won't always be level going down the road but this gives me the max amount of usable fuel and will need to take into account the hill situation when deciding when to fill up and how level the bus was when last filled. Part of the reason for doing this was to use a calculator program to determine the Distance-To-Empty based on current odometer reading. Using this info I can determine if I can make it to the next planned fuel stop. This is all base on an average MPG so if driving in high head winds or hills must also consider that.