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2018 Outback Limited, 2.5 litre, automatic
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No. The fuel pump is cooled (and lubricated) by the fuel running through it. Cooling is independent of fuel level in the tank ... right up until the pump starts sucking air.
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The heat is generated in the electric motor, not it the pump/impeller area. Things would get pretty exciting, pretty fast if the electric motor was cooled by gasoline. ;)
 

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'15 Outback 2.5i Premium
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The heat is generated in the electric motor, not it the pump/impeller area. Things would get pretty exciting, pretty fast if the electric motor was cooled by gasoline. ;)
Not really. Pure gasoline won't burn - oxygen is also required, and it has to be within a certain range of fuel/oxygen mixture ratios. Inside the tank (and the motor) the mixture is too rich.

Anecdote: when I worked for a contractor handling government aircraft, we were required to pump the fuel out of the tanks before parking them in the hangar because our facility did not have the foam fire suppression system required for fueled aircraft. At first this seemed counterintuitive to me since I thought a full tank would actually be safer than a nearly empty one (you will not get all of the fuel out). Apparently, even in this situation there still isn't enough oxygen in the tanks to be a hazard, and some of those are pretty big tanks. Live and learn.
 

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4th & 5th 2.5L Outbacks: new '19 & '14 with 75k. Traded '[email protected] yr 112k, '[email protected] 155k, '[email protected] 155k
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This doesn't mean you are in imminent danger of stalling, however you should refill as soon as you can because you run the risk of sucking up the crap at the bottom of your tank.

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You are ALWAYS sucking the "sucking up the crap at the bottom of your tank". THAT is where the fuel is ALWAYS being sucked from, LOL! Otherwise we'd run out with GALLONS left in the tank.
 

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4th & 5th 2.5L Outbacks: new '19 & '14 with 75k. Traded '[email protected] yr 112k, '[email protected] 155k, '[email protected] 155k
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Also, my experience with five OBs ('99, '04, '11, '14, and '19) is that there MPG estimate is ALWAYS about a gallon higher than actual MPG calculated by miles driven/gallons added. No idea why the computer claims I'm getting better mileage than I actually get but it has been consistent over 23 years varying somewhat fill up to fill up but the computer is always a gallon or so above actual.
 

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2016 Outback Premium 2.5 CVT w/EyeSight+SRVD
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Things would get pretty exciting, pretty fast if the electric motor was cooled by gasoline.
That's exactly the way it works. Refer to the illustration posted earlier. Gasoline, liquid or vapor, will not burn unless there are copious amounts of oxygen (e.g. air) present.
 

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To be safe I would never go below 90 miles. Especially if you are on a major highway. You never know when you might get into an accident related traffic stoppage.
Smart man! I’ve been caught in traffic with little fuel left. I don’t want to take chances any more.I look for fuel whenever I get below 3/8 of a tank left
 
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