When my mom bought her 2006 Prius the salesman told her NOT to let the tank get down below 2 bars because the tank might implode. It sounded kind of crazy to me but is there any truth to this?
Many of us have let our Gen II's go below 2 bars and never had an implosion... The Gen II in the US did have a bladder tank and not a regular tank, but still no implosions. The Gen III now has a regular tank. This thread would best be served in the Gen II forum so it is getting moved there.
The tank will not implode. The danger of letting the tank get too low is you will RUN OUT OF GAS. You may be able to limp to a gas station on electricity, but you risk damaging the big battery. Maybe you should should let her believe that the gas tank will implode. That way you will make sure you don't run out of gas.
And note Doc's emphasis. This risk is much greater on Priuses with bladders than people are accustomed to on other cars. The bladder makes refills and the gas gauge very erratic.
The Gen I/II bladders are predictable, just non-linear. I seem to notice a bell curve in the consumption rate as indicated by the fuel gauge. When I fill up, it stays at 10 bars for a very long time. Bars 9 and 8 stay around for awhile too, but then it drops from 7-3 pretty quickly. 3 and 2 stay around for awhile, and then it's 1 for even longer (though not as long as 10). I almost always fill up right after the warning starts flashing. It's usually around a 9 gallon fillup, so there's still plenty of emergency gas left when the warning is flashing.
The OP has a 2010 so I would disagree about moving the thread here. But whatever. No the gas tank won't implode. But if you run out of gas you -can- shorten the life of the traction battery. Once probably won't hurt, but don't make it a habit. If you do run out of gas don't drive it very far in "EV" mode. This is how you can shorten the life of the traction battery. From fo0bar: "I almost always fill up right after the warning starts flashing. It's usually around a 9 gallon fillup, so there's still plenty of emergency gas left when the warning is flashing." Unless the emergency requires more than 1.5 gallons of fuel. I still don't understand why people run the tank so close to empty. Maybe I'm just too "Swiss like" (always ready for anything, never caught short). I fill up at 1/2 tank whenever possible.
