T-89
T-85/89 had a 4th gear added and became T-10.

T-89 is a big veefy 3spd used with many early-mid '60s engines.

T-89 also used by Ford (w/ overdrive) (390) and by Olds mid '60s. (394)

T-89 (w/ overdrive) Ford was the last to offer them in '71 pickups.

T-85 (basically the same tranny as T-89) was also used with Dodge-Plymouth 426 engine in '64

T-10/85/89 all had the 9 bolt side cover , but the T-89 shift arms were (stagered ) not inline like the T-10 & 85.

T-89 and T-10 bolt patterns look very similar also to '49-'64 Ford pattern.

T-89 was fitted with a BW overdrive unit on the rear. These didn't bolt to just any tranny, there was an adapter about an inch thick (25-26 mm) that went between the tranny and over-drive unit. The output shaft of the tranny was a short length and splined to fit into the over-drive unit as well.

The T-89 also was used with the over-drive in the V8 torque tube cars.