B762/763 to small for longer routes?

[Mr. Pete]

How come I keep getting warning, that B762 or 763 are to small for 3000+ nm routes, if someone is flying there with for ex. A310?

Both planes are wide body, B763 even is having longer range and can carry more pax than A310?

[LemonButt]

Because it is based on fleet group and not model.  The A300 has 300 seats and is significantly larger than the B767.  Also, the warning is just a warning--you can typically fly the route without penalty.

[Mr. Pete]

Got it. Thanks!