do i need to start a new game in order to play the phantom liberty dlc?

[ZEEK (Trained Navy Seal)]

i think i have a save right kinda near the end of the game were you meet the ariska lady in her apartment if it matters

[almagnus1]

Nope, you can wander off to that part of the city and play through Phantom Liberty then go right back to that decision.

[Zebedee]

You'll log back into your save and find a message to reply to which will trigger the quest chain to get into Dog Town. It was designed so that existing saves in the late game could just dive into it, like almagnus1 says.

[Nar!]

I installed Phantom Liberty in the middle of my game. It seamlessly integrates with the base game. You'll get a call by a mystery character which you can accept to help and thus begins your Phantom Liberty journey. You can bounce back and forth the base game missions/gigs etc, and those in Dogtown.

Also note that starting fresh also presents a more robust experience, as you'd get the call right after a certain mission in the base game and it plays really well that way too. But yes, feel free to start Phantom Liberty even if you're 90% complete with the base game. As long as you're playing the 2.0-2.1 version of the base game that is. Phantom Liberty is not compatible with 1.6, I was told.