How to Identify a B Series Transmission
- 1). Count the number of teeth on the main planetary gear (the pinion gear that meshes with all the other gears and shaft to turn them). Write the number of teeth down on a sheet of paper.
- 2). Count the number of teeth on the second gear and write it down. Divide the number of teeth in the pinion gear by the number of teeth in the second gear. If the sum is 1.90, then continue on with the identification process. If the sum was 2.105, and the gearing is changed through a cable hookup, then it is a B16A (cable) transmission. If the control of the gearing is hydraulic, it can be either a B16A2 or B16A3, which are interchangeable.
- 3). Count the number of teeth of the gear that is used to turn the rear-axle drive shaft. (See the vehicle's owner's manual for its location in the transmission). Divide the pinion gear teeth number by the drive shaft gear number to arrive at the final drive ration (n.nnn:1). If the result is 4.266 with hydraulic controls and there no synchro mesh gears overlaying gears 2, 3 and 4, then the transmission is a B18B1. If it is a 4.266, cable-controlled and with no synchro mesh gears, it is a B17A1. If the result is 4.785, then the type is a B18C-JDM Type R. If the result is 4.40, continue with the process of identification.
- 4). Measure the diameter of the second gear with a ruler. If the gear is larger than 3 1/2 inches, then it is considered a long gear and the transmission identity is a B18C1. If the gear is smaller, then the transmission type is a B18C.
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