Unlockables not working?

i completed game once and dot seaperate ways complete twice , once with c.t. now im playing the game again and for some reason the merchant dose not sell the chicago t. i just rescued ashley and she has armor but i still cant get the chicago t. why, did i do something wrong, will it be for sale later in game? wtf im pisssed , i loved using the c.t in seaperate ways now i cant. someone please help, my last resort is to try to beat the game a seond time to get it. please reply p.s im playing ps2