Best definition
The Wtfbus, is like the Stfu truck, and the legendary “FailBoat”. It is said normally in place of “Z0mgwtfh4xbbq” thus

to save time. It is roughly as long as the “Shortbus” but three inches longer so people don’t mix the two up. It can be found in the southern parts of New-Mexico, riding high on the roads of “WtfLane”. Do not confuse this with the STFUhighway, or the FailLake.

Fred: I r kan hazez da bucket?

Eric: WTfBUS?

Fred: 😀