The Spectra sender I bought last month was made in Mexico, according to the label on the box.
The thing about fuel senders is that they sense the level of fuel in the tank, not the quantity, because the sensor floats on the fuel. The problem with gauge/sender linearity in our A-bodies has a lot to do with the shape of the gas tanks. Fuel level in those tanks does not have a linear relationship to fuel quantity because the bottom part of the tank holds the majority of the fuel (top part is smaller to fit around the spare tire well). When you've used the the first third of the fuel, the fuel level is actually half or less the level of a full tank. That's why a "linear" sender and gauge will indicate a fuel level that is lower than the quantity of fuel remaining in the tank, just as we see with these replacement senders. The OEM "non-linear" sender wiring (plainly visible in my OEM sender) was probably engineered to correct gauge readings for the shape of the fuel tanks.
But, then, what do I know? O
NOT a SLAM just a sharing of facts OK?
OK the linear vs NON linear electronic property of the variable ground sending unit HAS ZERO to do with the shape of the tank. ALSO the engineers at Chrysler accounted for the shape of the tank and placed the sender and shaped the sender to read the tank as it was designed with the spare tire indent, width height and depth included.
ALSO from the MR. Wizzard science tv series in the 50's & 60's to Bill Nye the science guy 70' & 80's tv series will all tell you, the shape of the container of a liquid has no bearing on how full or empty it is!!! The indent at the top of an a body tank ONLY displaces a certain amount of liquid residing in the tank. Therefore the sender is shaped to account for that so that the half tank mark is exactly where it is supposed to be. ANd given the size of the indent, I am certain that the half full mark is well below the physical middle of the tank... c'mon guys...do you REALLY think that was not considered when this tank and sending unit was being engineered? GEEZE
The linear vs non linear property of the sending unit is all about WHAT KIND OF SIGNAL is being sent. The signal from the sender needs to match the signal that the gauge can accept to properly show the level. The gauge and the sender MUST BOTH be either linear or NON linear, they MUST match, or your readings will be way off!
THE TROUBLE IS the primary re-popper of sending units makes ONLY LINEAR sending units ( not equal to OEM stock equipment, which was NON linear) and the GAUGE manufacturers today MAKE gauges
that are pretty much ALL NON LINEAR. HENCE THE GREAT MISMATCH causing all the erroneous fuel readings.
PLAIN & SIMPLE the aftermarket sending units are NOT compatible with the aftermarket gauges!!....if you have a decent stock sending unit, your stock AND your aftermarket gauges will work perfectly as designed....because the stock senders are NON LINEAR JUST LIKE the aftermarket gauges and the stock GAUGES...THEY MATCH!!
You cannot, with any degree of success, simply MIX & MATCH linear with non linear...they must match or they just don't work as designed and your readings will be all over the dial.
AND YES it does register the quantity via the hash marks on the gauge..and the position of the float and the corresponding position of the variable resistance ground, Hence. if you have a 15 gal tank, half way is 7.5 gallons a 1/4 of a tank is 3.75 gallons, 3/4 of a tank = 11.25 gallons and so on..... so the shape of the tank means nothing, because it is accounted for with the shape & position of the sending unit...savvy? NO fuel gauge has ever been 100% exact but if you are reading 1/8 of a tank and you still have better than 8 gallons in there....that aint just NOT exact that is WAY OFF !!!
NOT exact is about a gallon to a gallon & a half....Most people that run out of gas do it because they ride on E for too many miles, typically it is not the fault of the gauge but more the fault of the NUT behind the wheel
I have had 18 A body's in my life and NOT ONE of them with a stock gauge and sender has ever registered anything like what you are describing .....
" When you've used the the first third of the fuel, the fuel level is actually half or less the level of a full tank."
The NON linear wiring in an OEM sending unit corrected nothing, it was simply wired to be MATCHED to the gauge!!! DO you REALLY THINK IN THE 1960's they even considered designing a sending unit that electronically "corrected" anything? Hell when you parked on an angle in the driveway the gauge read something completely different than when you were on a level surface!! If that sending unit corrected for the level of fuel in the tanks how the hell did the gauge read a different level in the driveway?.... There was NO "corrective" sending units back then.....you've been readin too much RUBE GOLDBERG LOL