Each bar equals one gallon of gas in my experience. The last bar starts flashing when down to the - last bar. So one may believe they have a 10 gallon gas tank. Owners manual says 11.9 gallons though. So why did Prius make it appear that it has a 10 gallon gas tank? A lot of cars issue warnings when the driver is down to 50 miles of gas. Prius last bar flashes when one likely has over 120 miles of gas. Prius take some getting used to.
Owners of the previous prius generation kept getting stranded because they won't fill it up when it was much accurate, I mean they said the head space was too slim. To minimize that, the turd generation was built with larger headspace, point fingers at 2nd generation owners
It is a safety margin, or reserve, to reduce the number of people who get stranded by fuel starvation. I've never had one of those cars with a warning at just 50 miles. All (but one) of my pre-Prius cars had at least 100 miles of reserve. (The single exception had negative margin -- it ran dry with the fuel needle still above E.) Since getting my first Prius, I now have a Subaru that gives its first (of 3) warnings at about 75 miles. Safety margin is necessary because fuel gauging isn't perfect on level ground, gets worse when the car is tilted (front-back and side-to-side), and fuel consumption is far move variable than most people realize (weather, temperature, water-snow-slush on road, wind, mountain climbing, external racks, cold starts, short trips, etc.). Most people are not good at accurately mentally figuring fuel consumption in those degraded conditions. If the fuel gauge was truly "accurate" on average, then a lot of people cutting close to the limits would be caught by the unplanned negative swings of those variables. Then the Customer Support call centers would get hit with many angry owners claiming -- correctly even -- that "the Distance To Empty gauge said it had enough gas to get there, but it ran out early, stranding me in a remote place in the mountains without mobile phone coverage on a dark and stormy night!" Some people will run dry regardless. Toyota puts in enough margin that no one can legitimately claim insufficient warning. Think of it as "customer expectation management". There are many other elements of this built in to most cars, to make owners feel better and reduce complaints. Where I occasionally drive, 50 miles warning is simply inadequate:
All well and good but I actually believed I was about out of gas and acted accordingly during a long trip. Knowing I had gas would have changed a lot of logistics. Ten gallons doesn't go very far when towing a 1400 lb camper. I'd have never suspected I still had a few gallons without reading the manual.
Are you trying to tell us that you get OVER 60 MPG with your car ? Doubtful. ALL cars show "empty" before they really are........to try and help keep people from doing stupid things. Obsessing over exactly how each model accomplishes that is........obsessive. AND.....making one or two "extra" stops for gas during your trip is.....NOTHING.....in the overall scheme of things. Driving more than 500 miles straight without stopping is NOT a good idea, even if your bladder will allow that.
That safety margin won't go very far in that condition either, and depending upon it carries added risk. So "acting accordingly" is not a wrong choice in circumstances where running out of fuel causes a significant problem. Here is the best Gen3 fuel tank capacity test thread, though you can get everything you need from just the base post and skip the 487 replies: [WARNING] Running out of gas (Gen III) | PriusChat ... or the vehicle specifications list in the new car brochure, or the Monroney sticker (required window sticker on new cars), or Fuel Economy, or ... It become quite obvious when one compares the listed tank capacity to the gallons pumped during refills. This isn't about not making bladder stops, this is about detouring or changing routes or plans in order to get to available fuel before running out.
You are assuming that. That is not exactly what he said. I do find it rather odd that he seems not to have figured out how it works before his long road trip. Unless he just acquired the car and immediately hooked it up to something WAY over the engineered towing capacity and just took off on a long trip. The result could have been much worse.. But the whole story really doesn't make any sense if you think it through. It seems he is saying that he actually DID plan his stops a bit sooner than would have been necessary......if he had known the tank was bigger. That is NOT a problem. Just a minor annoyance.......maybe.
RULE OF THUMB: In average highway conditions/driving, when the DTE hits ZERO miles to go, you can always go 50 miles more. There was a thread on this a couple of years ago. SECOND RULE OF THUMB: A thread about the fuel gauge "bars" or "DTE" gauge brings out the worst in people. Your actual question will be ignored and they will tell you how stupid you are for driving after X bars or when there are Y miles left on the DTE. Or they will flame you for driving Z miles without stopping, or say you are silly for not wanting to stop for gas more. Not sure why people get their knickers in a twist on this subject, but it happens every time.
Drivers towing 1400 lb campers should adjust this rule downward in proportion to their towing vs non-towing MPG.
The camper weighs 1200 pounds which it pulls exceedingly easily. I figure ~200 pounds of gear. The mpg went to: ~26 on the interstate ~32 on rural roads Think I averaged 28 overall. With diligence (slower interstate driving) I could easily go another 50 miles after the estimate reads zero. Others will not do as well. I am happy in the right lane going slower than some. Especially when on a scenic trip though the Rocky Mountain region. Prius is widely rated at a 1500 pound tow capacity. That sounds about right. Though I wonder about the 1.5 liter models. The key issue, to date, is the accelerated wear and tow to the brake linings. It still stops quite nicely but the brake pads are not large. I will look at the brake pads when I replace the tires in ~ one week. Already have new pads - Prius pads are not expensive. Hope they are easy. I know the pad wear is significant because of the brake fluid reservoir change after the trip. Being so low to the ground is a nice safety feature, I felt good towing the camper. I think the aerodynamic hit was the worse though teardrop are not bad in that respect. As for the haters and derision I see so often - I've been driving it for two weeks.
Right -- the 50 miles after zero DTE is only under average conditions -- towing is definitely not average in a Prius!! Right. The OP is confusing Gen 3 with Gen 4. The owner's manual for Gen 3 specifically says no tow capacity not even a little. Gen 4 has a maximum towing capacity of 1,598 pounds. When publicizing the change, Toyota noted "heat management measures that have been introduced in the hybrid system's main electric motor-generator and the differential" permitted the new towing capability.
Yeah even 4th, North American at least, excerpt from 2016 Owner's Manual: Basically, not even a trailer hitch just for bike rack, etcetera. That's a little draconian, but... Maybe you're thinking of European Toyota stance? Seems to me some places they condone towing for 4th gen.
Yeah, there have been some articles on that and the politics involved. It's the exact same car but when speaking "European" Toyota says "AOK" and even has pictures of the Prius towing a small teardrop trailer.
