I urge you not to create one. I have been on two other car forums that were killed by Facebook pages stealing all the traffic. Let facebook be facebook and forums be forums. Forums make WAY more sense with the organization they allow than facebook does for car groups....trust me.
The thing is, though, that trustworthy people never actually ask you to trust them, because they don't have to. I'm not saying you're not right, and I totally agree that this site doesn't need a facebook page to thrive, I'm just saying, never trust a man that says, "trust me."