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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.
View attachment 526148
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.

View attachment 526078
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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Outback H6, Range Rover,
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For the first time since I bought my 2019 2.5 OB, I ran the tank down to almost empty. I was at 60-miles-left per the low fuel warning, but I was 35 miles from home after a 400 mile trip. Pulled into the driveway with 30-miles-left for fuel. This morning the warning still read 30-miles-left. My first stop was a gas station which is about 1 mile away and down hill.
About halfway to the gas station, the miles left indicator went from 30 to zero. Actually the indicator was just 4 hyphens.

Has anyone else with a Gen 5 or specifically a 2019 experienced this moment of being perplexed by lack of info? The question loomed in my head; How far can I go before the engine dies?

I can leave it to chance given that the night before it indicated 60 miles of gas left with 35 miles to home.
Shouldn't we expect a bit more accuracy ? Is this a know problem with the fuel gauge or tank sensor?
What I do, take jerry can with petrol with you, and when the DTE indicated 0, zero your tripmeter and keep driving till it stops.
I had a car I could do another 50km's after the DTE said 0.

It's a bit of a kerfuffle, but it gives you piece of mind
 

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2008 OB Limited 2.5i, Portland OR USA
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With regards to the original question posted in the title of this thread:
  1. Enough that you can stay out of trouble if you so choose.
  2. Not enough to allow you to push things to the point where you'll be able to get a meaningful answer to the question.
:)
 

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2018 White Outback Touring 2.5i
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For the first time since I bought my 2019 2.5 OB, I ran the tank down to almost empty. I was at 60-miles-left per the low fuel warning, but I was 35 miles from home after a 400 mile trip. Pulled into the driveway with 30-miles-left for fuel. This morning the warning still read 30-miles-left. My first stop was a gas station which is about 1 mile away and down hill.
About halfway to the gas station, the miles left indicator went from 30 to zero. Actually the indicator was just 4 hyphens.

Has anyone else with a Gen 5 or specifically a 2019 experienced this moment of being perplexed by lack of info? The question loomed in my head; How far can I go before the engine dies?

I can leave it to chance given that the night before it indicated 60 miles of gas left with 35 miles to home.
Shouldn't we expect a bit more accuracy ? Is this a know problem with the fuel gauge or tank sensor?
Just a guess but when going downhill, what's left of the gas might shift around causing the float to bottom out. My low fuel warning light used to turn on with 0.3 gallons left in the tank. (I pumped 18.2 gallons into the tank) After the recall the low fuel light now turns on with 3 gallons left in the tank.
 
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