Fuel Tank Capacity: A Sanity Check

[Bodeco]

Mornin' all....

 

I recently have finished up my first two tanks of gas in my new 1996 Outback Wagon. Much to my horror, it appeared that I got about 15 miles to the gallon on my first tank... I hit the big 'E' with only about 240 miles on the trip meter. I was pleasantly surprised once I filled up to find that the tank only held a little over 10 gallons.

 

From everything I have read, this vehicle should have a 15.9 gallon tank... is this correct? Just want to make sure I'm not losing my mind here. I guess this means that my fuel gauge is sorely inaccurate?

 

Thanks,

 

-Alan

[Manarius]

The gas gauges on these cars are notoriously inaccurate. Only thing I'd trust is the low fuel light.

[OB99W]

[...]From everything I have read, this vehicle should have a 15.9 gallon tank... is this correct? Just want to make sure I'm not losing my mind here.

Your memory/sanity isn't an issue. The tanks do hold about 15.9 gallons, unless there's a big dent somewhere.

 

 

I guess this means that my fuel gauge is sorely inaccurate?

As Manarius said; however, some have mentioned here that after adding Techron fuel system cleaner to the gas tank, the gauge was more reliable. It probably wouldn't hurt to check electrical connections at the rear as well.

[Seahag1978]

Ironic that this should come up. I was wondering the same thing this past weekend. We took an 800+ round trip.

I did notice that I drove 100 or so miles before the needle moved, then it dropped to three-quarters in one swoop. That's pretty much what my older models did. I figured Subaru would have improved that on the newer ones. Guess not.

My mileage varied drastically on the way there because of the hill climbing and construction slow-downs. The descending return trip took one full tank of gas at a constant 75-80 mph with a/c on.

 

The car is an '05 Baja 5 sp. turbo.

[Bodeco]

Thanks for the replies... actually I just put my second jug of Techron in on the way to work this morning. Hopefully that will help some.

[Bodeco]

Oh yeah... so my tank is definitely 16 gallons right? There were no limited models that had a smaller tank or anything crazy like that? Knowing my luck that wouldn't surprise me at all.

[idosubaru]

nah, the 15.9 gallon capacity is common, even XT6's built in the 80's have 15.9 gallon tanks. there are some variances, but yours is 15.9.

[Manarius]

15.9 gallons is almost exactly 60 liters, which is why Subaru uses that size on almost all their vehicles.

[vic/se]

15.9 gallons is almost exactly 60 liters, which is why Subaru uses that size on almost all their vehicles.

 

 

My wagon as a 16.9 g tank or close to 64 liter

[firstwagon]

My wagon as a 16.9 g tank or close to 64 liter

 

You may be counting the volume of the filler pipe. Offical size is 60 litres.

[forester2002s]

When I measure my fuel consumption, the capacity of the fuel tank does not enter into it.

 

I just fill up completely each time. And I reset the trip-odometer to zero.

Then I use the current fill volume and the distance since the last fill to calculate either: Litres*100/km (to give me L/100km); or else: miles/gallons (to give mpg).

 

It's that easy!

 

Having said that, I find that a single reading is not really accurate, because the level of the final 'fill' is variable. Some pumps 'click off' too early, and others too late with the gas up into the filler tube.

So my spreadsheet also calculates the fuel consumption over the last five fills. I call that a 5FMA (5-Fill Moving Average). I find that useful to observe long-term trends.