Today we bring you a most fascinating curiosity. Most fascinating if you are sufficiently curious or geeks of the motor world – and geek is not pejorative, it is a compliment. Normally we do not pay much attention to the car’s fuel level indicator, beyond its normal function. It’s a needle or a digital indicator, and little else, right? What if I tell you that the Nissan 300ZX Z31 had two fuel level indicators? What was this duality due to? Did they have two fuel tanks? The answer is not what you think.
In the photo that accompanies this article you can see what we are talking about. A needle indicates the fuel level, with its usual scale of F (full), 1/2 and E (empty). Below it, a second scale oscillates between 1/4, 1/8 and 0. This very curious double system was mounted in the Nissan 300ZX Z31, but also in the Nissan Fairlady 280Z from the late 1970s, and even in some light pickup trucks known as the Nissan Hardbody – again, in a time frame that ranged from the mid-1970s to the mid-1980s.
The second needle did not appear until the fuel level dropped below a quarter tank.
The function of this second watch was know more precisely how much fuel we had left in the tank when we reached a quarter of its total capacity. It was then when the second needle started moving, allowing us to know precisely how far we could go. Or so that drivers with a lower perception of risk, know how far they could drain the fuel that was left in the tank. The idea was to offer more information and safety to the driver, especially in GT cut cars with which long journeys could be made.
The most striking thing was that it was also available in some simple pick-ups, which together with the brand’s sports cars, were surely the cars where fuel consumption was not so observed. Be that as it may, this curious system was not replicated by any other brand, and It wasn’t even available on luxury vehicles. Now, there have been other vehicles with a double fuel gauge, but we are talking about heavy-duty or commercial vehicles with two fuel tanks, as is the case with certain pick-ups of American origin.
Each mark on the second indicator corresponded to just over two liters of gasoline.
The technology behind the dual fuel gauge was not trivial and possibly more expensive than accountants wanted: required the installation of a double flume system, with its double linkage and its wiring. Possibly that was the reason that the system was not equipped in more cars from now on, in addition to making any repair more expensive. In any case, it is a delicious curiosity that warms the heart of any lover of “dark Petrolheadism”. Of course, courtesy of our friends at jalopnik.