first digit: ring gear diameter

A 138mm
B 145mm
C 6.25"
D 6.62"
E 7.1"
F 7.5"
G 8"
H 9"
J 9.25"
K 9.5"
L 10.5"
M 12.5"
N 13.5"
P 14"
Q 12"
R 162mm
S 6.38"
T 6.7"
U 6"
V 10.6"
W 15.5"
X 142mm
Y 158mm
Z 202mm
- no ring gear = FWD

Second, third digits: gear ratio

01 3.30
02 3.36
03 3.545
04 3.556
05 3.70
06 3.889
07 3.90
08 4.111
09 4.222
10 4.375
11 4.444
12 4.625
13 4.79
14 4.875
15 5.125
16 5.286
17 5.60
18 5.714
19 5.833
20 6.167
21 6.667
22 6.78
23 6.833
24 7.64
25 4.556
26 5.571
27 3.364
28 4.30
29 4.10
30 3.727
31 3.909
32 6.591 or 4.807
33 7.503 or 5.583
34 6.781 or 4.786
35 7.636 or 5.60
36 4.778
37 3.583
38 3.417
39 3.154
40 5.375
41 3.308
42 6.500
43 3.550
44 3.214
45 3.533
46 2.928
47 3.944
48 3.356
49 3.729
50 3.400
51 3.736
52 3.722
53 3.250
54 3.941
55 3.333
56 2.821
57 4.058
58 3.238
59 3.234
60 3.519
61 2.724
62 2.892
63 2.655
64 4.312
65 3.837
66 3.071
67 3.526
68 3.095
69 4.176
70 5.857
71 2.962
72 3.949
73 4.285

Fourth digit: no of pinions, ltd slip-yes/no

Code	pinions	ls
2	2	no
3	2	yes
4	4	no
5	4	yes