WotLK GearScore for Heroic dungeons?

[Bloodrow]

What GearScore do I need to become eligible for 5 man Heroic Dungeons?

[3nTRoPy]

The rule of thumb is an average item level of 185 or more. It has no direct connection with gearscore, that is simply a concept introduced by an addon. You can be 2.4k gearscore and able to enter rdf hc, and you can be 4k and unable. Keep in mind that heirlooms provide a lot of gearscore, but they have item level 1, empty item slots count as an item of level 0.