This chart was taken from the
http://www.tacomaterritory.com FAQ section.
First digit:
A = 7.5" ring gear
B = 8" ring gear
Next two digits: 01 = 3:42
02 = 3:58
03 = 4:10
04 = 4:56
05 = 3:15
06 = 3:91
Last digit:
A = 2 Pinion, Open
B = 4 Pinion, Open
C = 2 Pinion OEM Limited Slip
Submitted by David Hale
Using the above codes would result in the following axle codes:
B01A 3.42 2 pinion open 7.5" ring gear
B01B 3.42 4 pinion open 8" ring gear
B01C 3.42 2 pinion posi (OEM limited slip)
B02A 3.58 2 pinion open 7.5" ring gear
B02B 3.58 4 pinion open 8" ring gear
B02C 3.58 2 pinion posi
BO3A 4.10 2 pinion open 7.5" ring gear
BO3B 4.10 4 pinion open 8" ring gear
BO3C 4.10 2 pinion posi
B04A 4.56 2 pinion open 7.5" ring gear
B04B 4.56 4 pinion open 8" ring gear
B04C 4.56 2 pinion posi
B05A 3.15 2 pinion open 7.5" ring gear
B05B 3.15 4 pinion open 8" ring gear
B05C 3.15 2 pinion posi
B06A 3.91 2 pinion open 7.5" ring gear
B06B 3.91 4 pinion open 8" ring gear
B06C 3.91 2 pinion posi
Note: The following has not been verified:
BO7A 4.56 ? 2 pinion open
3.42 (automatic) ? 2 pinion open
3.91 (manual) ? 2 pinion open