At 08:37 AM 1/30/2009, Kim Brennan wrote...
>This can vary, vanagon to vanagon.

The fuel gauges can be adjusted. There are two holes in the back, with
a mechanism which can be turned. One adjusts offset, the other adjusts
range, but they interact, so it is an iterative process. That obviously
won't help if you have a bad sender, though.

>Also, since the fuel guage is driven by voltage, if you have low
>voltage from your alternator (or are running on battery), the gauge
>will read lower.

The fuel gauge is driven through a 10V voltage regulator, so if your
supply voltage is so low as to effect the fuel gauge, you have more
serious problems than an improperly reading gauge.