2nd Gen Non-Engine/Transmission fuel gauge problem?

[vaicase]

my fuel gauge on my 94 when i fill it goes to full,the in75miles or so it drops to3/4the in another 50more it drops to empty then the light comes on. when i fill it the most i ever put in is 16gallons. so today i took the box off and took out the sending fuel unit. the scale is very dirty so i cleaned it. is the scale the problem?i am talking about the thing with two screws that the float hooks to. i heard the diesel eats the material off the scale?can i get just the scale?or do i got to buy the whole thing?i see them on ebay 125. 00 plus shipping. but can i just buy the scale?does anyone know what its called?the rest off the fuel system is just the way it should be. by the way the truck has 2600000 miles thank you.

 

[vaicase]

by the way i forgot to mention the float is chewed up. could that be the problem?thanks again

 

[John - K5AWO]

The "scale" you are referring to is the rheostat or a resistor that has a sliding contact point on it. If it has corrosion on it, it will not work correctly. Also, if the float is not in good condition that will cause it to go to a "low" fuel condition quicker than it should.

I've only bought two of those things in the past 40 years. Both times I had to buy the complete assembly. I suspect you will too.

 

[Joe G.]

The part number I used at Dodge for the sending unit is 4797738. The price was a little over $70 bucks a couple of years ago.