Don't know about Synchros, but on Herbie, 85 Westy I know exactly!
Last summer returning from the High Country Bus Festival in Boone, NC
my navigator gave me the wrong turn (Wasn't my fault, right?)  that
put us on a back country road.  I started looking for gas stations,
but there were none to be had.  In a while we started coughing and I
thought that we would be walking a while.  We crested a hill and it
quit!  Coasting down and around the corner we came to a little
country store with..........a fuel pump.  Yea! :-)

Any way, from completely empty to full was 16.45 gallons on the pump.
I realize that running completely dry is not good for the fuel pump,
and usually fill at the next station after the light comes on.

Well, about six months after our country test on the capacity of the
tank, I ran out again!  This time there was no light so I thought I
was ok, and the light has not worked since.  Doubt if there is a
connection, but that little light was a friendly reminder to pull
over and gas up.  Now I just go on mileage and fill up at about 200
miles.

Jim in Atlanta

[text/enriched]
Don't know about Synchros, but on Herbie, 85 Westy I know exactly!
Last summer returning from the High Country Bus Festival in Boone, NC
my navigator gave me the wrong turn (Wasn't my fault, right?)  that put
us on a back country road.  I started looking for gas stations, but
there were none to be had.  In a while we started coughing and I
thought that we would be walking a while.  We crested a hill and it
quit!  Coasting down and around the corner we came to a little country
store with..........a fuel pump.  Yea! :-)

Any way, from completely empty to full was
<fontfamily><param>Geneva</param>16.45 </fontfamily>gallons on the
pump.  I realize that running completely dry is not good for the fuel
pump, and usually fill at the next station after the light comes on.

Well, about six months after our country test on the capacity of the
tank, I ran out again!  This time there was no light so I thought I was
ok, and the light has not worked since.  Doubt if there is a
connection, but that little light was a friendly reminder to pull over
and gas up.  Now I just go on mileage and fill up at about 200 miles.

Jim in Atlanta