That's right. 4000 is the only one of 317 TTC air cars (including the 27 ex-Cincinnati air cars purchased second hand).
Pennsylvania Trolley Museum has 1138, 1467 and 1799 (ex-1613) out of 565 Pittsburgh air cars.
NCTM has Washington 1101, 1430 and 1540 out of 488 Washington air cars.
Of...