What would you do? #60 - Facing turn pot bet with trips

Full Tilt Poker $0.25/$0.50 Pot Limit Hold'em - 7 players
The Official DeucesCracked.com Hand History Converter

BTN: $22.50
SB: $98.05
BB: $43.40 - 53/3 @ 36 hands
UTG: $50.00
UTG+1: $56.50
MP: $42.10 - Donkey high VPIP / low PFR
Hero (CO): $50.50

Pre Flop: ($0.75) Hero is CO with 5h Ad
2 folds, MP calls $0.50, Hero raises to $2.25, 2 folds, BB calls $1.75, 1 fold
Trying to isolate the MP donkey, in position, I raise to discourage other callers. I get the two donkeys to call, though...

Flop: ($5.25) 6c Ac 2h (2 players)
BB bets $2, Hero raises to $6, BB calls $4
Flop far from the nuts, though I have a backdoor straight to go with my top pair.

Turn: ($17.25) Ah (2 players)
BB bets $17.25, Hero requests TIME, Hero folds
Here's where we get interesting. What am I hoping he has here that I can beat? A3, A4? Since the board is all low cards, I am certainly not going to be able to play the board as a kicker. Just about any Ace beats me here. I also feel as though my flop raise has adequately represented the strength of my hand. That said, did I allow the donkey to push me off the best hand?

Clearly I do not want to get stacks in with a naked Ace; his pot sized turned bet implies stacks.

Final Pot: $17.25
BB wins $16.40
(Rake: $0.85)