Adjust gas gauge?
 

After reading the "how many in-cab tanks" thread, I realized that my gas gauge has to be off because I filled it up from near empty the other day and only put about 9 gallons in it. On the bright side, I'm getting better gas mileage than I thought. However, I don't like the fact that I don't have accurate readings, which could be problematic on trips. Is there a way to adjust the gauge somehow to make it read correctly?

When I fill up the tank, the needle goes to the far right hash mark in on the gauge, but when I turn off the ignition the needle goes so far left that I can't see it in the viewing window. I figured that the far right mark was full and I would fill it up when the needle goes between the middle and left mark, but I'm starting to think that I'm off.

Re: Adjust gas gauge?
 

The guage should go past the full mark when full and go completely off to the left when the ignition is off. There is no way to adjust the fuel guage. If its not reading correct, you will probably need a new sending unit, or have the guage rebulit. The original guages and sending units are 0-30ohm

Re: Adjust gas gauge?
 

Re: Adjust gas gauge?
 

It seems like the easiest troubleshooting would be to replace the sending unit. How difficult is this? It seems like it will be pretty simple to do but I've never done it.

Re: Adjust gas gauge?
 

do like me and alot of others on here and use a yard stick. lol.

Re: Adjust gas gauge?
 

After thinking about it a bit you might be able to use a voltage regulator on the power wire to the gauge. The fuel gauge works kind of like an ammeter. If you cut the voltage down to maybe 5-6v you could get a more accurate reading. Using a variable regulator you could at least set it to let you know when its actually empty. I'll try to dig up a 0-90 ohm sending unit and test it out.