Nice draw OOP, should I be more aggressive

[Nate_Dogg]

Party 1/2 Full ring
Myself and opponent have full stacks
Opponent is somewhat loose/passive over 50 hands or so, but not terrible.

I limp in mp w/ 9h 8h
Opponent raises to $6 in LP folded back to me and I call
Pot = $15
Flop is 2s 5h 6h giving me a gutshot and a flush draw
I check to opponent and plan to check raise him pretty hard
However, he bets $6 or 40% of pot
I change my mind and call since he is giving me decent odds
Pot = $27
The turn is the Ts and I check to him
He bets $8 or 1/3 of the pot
Should I just call getting a decent price or try to push him off his hand right now?