Your gauge means nothing. You need to fill it up and do the math. Even then it may not be correct as MB odometers are often broken or not accurate, especially if its a 123 or 126.

I go 600mi on 19.5 gals on mine quite often. Weekly in fact.

__________________
Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)