Rear Axle Ratio Identification Codes

 CODE
 ENGINE
 RATIO
 TYPE
 TRANS
AK
327
3.36:1
Std
Manual or PG
AL
327
3.08:1
Posi
4-Speed
AM
327
3.36:1
Posi
Manual
AN
327
3.55:1
Posi
4-Speed
AO
327
3.70:1
Posi
4-Speed
AP
327
4.11:1
Posi
4-Speed
AQ
327
4.56:1
Posi
4-Speed
AR
327
3.08:1
Std
  4-Speed*
AS
327
3.70:1
Std
  4-Speed*
AT
427
3.08:1
Posi
4-Speed
AU
427
3.36:1
Posi
4-Speed
AZ
427
3.55:1
Posi
4-Speed
FA
427
3.70:1
Posi
4-Speed
FB
427
4.11:1
Posi
4-Speed
FC
427
4.56:1
Posi
4-Speed
* Wide Ratio
* Close Ratio