2007 Bluebird All American FE ride along

this bus is equipped with a 7.2 Caterpillar C7 inline 6 turbo diesel and the Alison AT545 transmission bus number 3 (spare bus) 8 is getting a warning light replaced. it's interesting that the spare bus is newer and a bit surprised that we got 3 instead of our other 98 bus 14 which is the sister to 8 and I believe it's also a spare. Please correct me if I messed up on the transmission information, I'm not sure it has the AT545.