how to tell which tranny

[putterspitt]

1989 thomas S1700 7.3 diesel has 1-2-3 D on the shifter
guessing its a 4 speed auto
anybody have an idea what came in these buses?

oh yeah its a shorty full body but a shorty

[frank-id]

Slide under your bus on the curb side. There will be a 2X3 tag on trans side near the oil pan. Your trans is a AT 543, based on the passengers. This unit is very dependable with good care. The unit information is AT means Allison Transmission, 543 means 500 series about 750 pounds torque, 4 speeds, 3rd change made on this design. Most trans use a very good spin off filter for low repair. It is a good idea to have and use a trans temp gage. The fluid should be bright and shiney... Frank in Idaho

[putterspitt]

appreciate the info, will slide under when it stops rainging
just put rebuilt injector pump on, ran ok with alot torque, seemed a little loud though
tks again