Villain is loose but somewhat passive. Take another stab on the turn like me thinking he is just "taking one off"?

PokerStars 1/2 Hold'em (10 handed)

Preflop: Hero is MP3 with , .
2 folds, UTG+2 raises, 2 folds, Hero 3-bets, 4 folds, UTG+2 calls.

Flop: (7.50 SB) , , (2 players)
UTG+2 checks, Hero bets, UTG+2 calls.

Turn: (4.75 BB) (2 players)
UTG+2 checks, Hero bets, UTG+2 folds.

Final Pot: 5.75 BB

Results in white below:
No showdown. Hero wins 5.75 BB.

I think it was played pretty damn good to me briachek. He could of had QQ or AQ and that K scared him off, but not you.

I'd be very happy with that result and not concerned on trying to squeeze out anymore money.

Playing it the way you did is much better. You are correct that when you're beat now, it costs the same regardless if you bet now and check the river, or check the turn and call the river. The difference is that betting now gives him the chance to fold , whereas checking gives him a free shot to hit a card that beats you. Checking and seeing an ace, queen, or jack on the river is a nightmare. The fold equity is key because I can't see you winning this hand at showdown if it were to get that far. If he has jacks/queens you have to bet the turn to win the pot.

I don't see any other way to play this hand.

You have 3 things going for you here:
1.Position
2.The 5th best starting hand in hold'em
3.A loose passive opponent (i guess this could work for or against you)

Pre-Flop:I agree, raise it up.
Flop:You were the pre flop aggressor, bet it u.
Turn:Looks safe to me, bet it up. If called, well since your opponent is so passive his actions may dictate your actions depending on what the river is. Obviously if he comes out firing on the river=fold, if he checks then check for the free showdown. I don't see any other way of playing this.