"Judah" wrote in message ...

I've heard several "urban-legend" style explanations for the uneven
drainage issue, and I don't claim to know which one is accurate. However,
they don't generally seem to drain unevenly enough to have any significant
impact on weight and balance...

The crossfeed issue on the 172 (why the left tank drains faster) is not
an urban legend. If you are a Cessna Pilot's Association member they
will send you a brief on what it is and how to fix it by tweaking the tank
vent.