The race cars you see on your TV during a NASCAR race may be made by the same company as a car you would see on the street, however NASCAR cars are very different. One of the most surprising differences between NASCAR cars and every day cars is that NASCAR race cars do not have a fuel gauge in them. Many parts of a NASCAR car are different from a regular car such as the headlights and brake lights, which are both just stickers. In fact, NASCAR does not even allow the race cars to have fuel gauges in them. Many factors led to this rule being made, but the main one is that with the steep angles and constant turns that a race track presents, the conditions for fuel measurement are simply not good enough.
NASCAR drivers do not actually need a fuel gauge in their cars. This is because NASCAR races are always a set number of laps, so drivers can figure out how many laps need to be driven before they go to refill their tanks. NASCAR never allowed actual fuel gauges, but instead used to allow a monitor that would give the drivers an idea of how much fuel they had left. That has since been banned, as NASCAR wants the drivers to be able to do it themselves. NASCAR dashboards are very different from what people are used to seeing in a normal car, but NASCAR cars are far from normal. Drivers have to manage many different things in their cars all while traveling at high speeds for long periods of time.
It is also extremely likely that a fuel gauge in a NASCAR race car would not even be as useful as people think. NASCAR race tracks have four angled turns that keep the car on an angle lots of the time. The car also bounces very often during races, which also would make it hard to read the fuel levels as the gas jumps around in the tank. Normal cars do not travel close to the speed or angles that NASCAR cars do, so it is very easy for a fuel gauge to work in those conditions. The conditions that a NASCAR environment presents make it nearly impossible to measure fuel, so even if NASCAR allowed it, having a fuel gauge would not give drivers quite the advantage it should.
Timing when to make a pit stop and when to refill your fuel tank are key in NASCAR, as drivers do not want to waste any time or any fuel. When drivers fill up their tanks, they try to use every ounce of fuel that they can before they go back to the pit crew for more. Doing this without a fuel gage is of course very difficult, but it is part of the strategy involved with driving a car in NASCAR. Many drivers practice with their pit crews and crew chiefs how far they can go with using a certain percentage of their gas tank. After doing this a few times, it actually becomes quite routine for a driver to know when to refill their tank.
Although NASCAR does not allow fuel gauges in cars, drivers usually have a good idea of how much fuel they have left before they need to start thinking about making a pit stop. With races having a set number of laps in it, drivers can calculate how many laps they need to take between pit stops, and after a while it comes naturally to some.
Just like everyday drivers on the roads, NASCAR drivers like to push their gas tanks to the absolute limit, especially when they are close to their destination, the finish line. It does not happen too often, but it is not unusual to see a driver come down the stretch of a race and lose a lead or lose a chance at winning. This happens when drivers misjudge when to refill their tanks and the end of the race gets too close to make a pit stop. When this happens, drivers have to hope that the fuel they have is enough to get to the end of the race, or else they could be putting themselves in serious danger to lose the race. This understandably is one of the least desirable ways to lose a race in NASCAR, as it shows some mismanagement on the part of the driver and their team.