Opponent is 34/6 over 154 hands.

Full Tilt Poker, $0.50/$1 NL Hold'em Cash Game, 8 Players
LeggoPoker.com - Hand History Converter

Hero (UTG): $111.80
UTG+1: $100
MP1: $40.45
MP2: $20
CO: $100
BTN: $83.70
SB: $107.55
BB: $120.85

CO posts $1
Pre-Flop: J A dealt to Hero (UTG)
Hero raises to $4, UTG+1 folds, MP1 calls $4, MP2 folds, CO calls $3, 3 folds

Flop: ($13.50) 3 T 4 (3 Players)
Hero bets $10, MP1 folds, CO calls $10

Turn: ($33.50) J (2 Players)
Hero checks, CO bets $22, Hero calls $22

River: ($77.50) 5 (2 Players)
Hero checks, CO bets $64 and is All-In

Does this make sense post-flop? Maybe it's not a good idea to play AJs in early position, but I'm more interested in the turn and river.

If it helps, his bet on the river was instantaneous. It just didn't seem like a bluff.

flop: what kind of player is MP1 who folded? I might get too timid lately, but I´d like to have a little reason to c-bet this with at least one loose player in the hand, 3way pot.

river: fold is fine here w/o reads. It´s a bluff sometimes but not often enough imo. Also, that´s not the kind of line they show when they mistakenly overplay {KJ,QJ}.

C/rai on the turn

at the very least bet it.

god i love you

No I def think crai turn is the best line. I would take that line with QQ, KK, AA as well.

Also, if you're gonna raise AJs utg, at least raise a little more with the CO poster.

yeah raise more pre if you are raising. I think vs 2 opponents, at least one of whom is loose and donkish, this is a bad flop to cbet.
as played I like a turn c/rai, idiots will often look you up pretty light. You didn't mention how aggessive CO plays but at 34/6 he is most likely passive and calling is most likely bad.

If he's passive isn't bet/bet/bet the way to go?

yeah touche. I've been saying a lot of stupid things in strat posts lately, most of my posting is done after I'm finished working for the day and I've already filled my body with drugs to put myself down for the night

Still though, I don't think its unreasonable. There are a lot of loose/passive preflop players that are going to make a "protecting my hand"/"finding out where I stand" bet or even a semi-bluff if we check the turn; sometimes they will get stubborn and look a c/r up real light after they've been "tricked."
Shoving the river, however, is a whole different story

What´s the villains supposed range for calling our turn c/r ai?