There is a ton of information on this problem if you do a search. Get a 0-100 ohm variable resistor, remove the sender wire from the gauge post, hook the variable res. to the gauge sender post and ground other side of resistor to gauge case. Turn key switch on, turn variable resistor until gauge reads empty. Turn key off, remove resistor and use ohmmeter to read its value. That ohm value is what your gauge wants to see for an m/t tank. Repeat above test for full tank, 1/2, 3/4, or whatever. For a 0-30 ohm gauge and a 0-90 ohm sender and do the math, you will find that putting a 47 ohm (a standard resistance value)in parallel with 90 ohms (full tank) will give a 30 ohm value to the gauge...great right. But then, when you reach 1/2 tank and the value to the gauge should be 15 ohms it instead will be 22 ohms which looks more like 3/4 tanks. WOW...I'm getting great gas milage with this new sender. Empty will be right on because of the zero resistance thingie, but when you get to 1/8 of a tank and start looking for a gas station, it had better be right up ahead. All-in-all its how you look at things. If you play horseshoes or throw hand grenades, then anything close counts. If you are a sniper...well, you understand. Good luck
