Wheel discussion aside...
This is something that always aggravated me about Gran Turismo. You simply choose manual or automatic, and every car you get just has whichever you pick. Even if you change your preference from manual to automatic, all your cars end up that way as well (like they got a magic transmission swap in your garage while you weren't looking). It's asinine.
It should go something like as follows: when you buy a car, you choose the transmission - and if it doesn't come with a manual or an auto or paddle shifters or whatever it happens to have in real life, you don't get the option - and you're stuck with it. (To be fair to casual or new players and little kids, you should get an option to let the computer make manual shifts for you, however.)