Rear Axle Identification

 

Provided by JOHN HUNTER, ROA #32499, Nisland SD (and the R.O.A. Library)
Originally published in The Riview Volume 2 Issue 6 Sept./Oct. 1996

1963 - Ratio is stamped on the bottom of the axle housing - two numbers - one above the other. Example: 3 over 2 is 3.23-1; 2 over 78 is 2.78-1. Locking axle (positraction) is identified by "X" in a circle on bottom of carrier flange.

Ratios available (all models): 2.78; 3.23; 3.42; 3.91.

1964 - Location same as 63. Ratios available (all models): 3.07; 3.23; 3.42.

1965 - Ratio and I.D. are stamped on the bottom of carrier flange. Example: an X inside a circle; Locking axle; PA ratio code; 203 - Manufacturing day of year.

1966 - Ratio codes located on bottom of right axle tube 3 inches from cast housing "X" in circle means locking axle.

1967 - Codes located on bottom of axle tube to right of axle center.

1968 - Location of code on bottom of axle tube to left of axle center.

1969 - Location of code is on the bottom of axle tube of left side 3 inches from axle center.

1970 - Location (same as 1969).
1971 - Location (same as 1969).
1972 - Location unknown.
1973 - Location unknown.

CODES (all models)
RATIOS
PA, PN
3.07
PC, PP
3.42
PD, PR or Ratio # Special Order *
*Special Orders: 2.78 - 3.23 - 3.36 - 3.58 - 3.91 - 4.45.
 
CODES (all models)
RATIOS
PL, PO, PK, PR 2.78
PG, PV, PJ, PM 3.07
PA, PZ, PN 3.23
PW, PY 3.42
PX, PS 3.91
CODES (RIVIERA ONLY)
 
NON-LOCKING LOCKING
RATIOS
PJ PM 3.07
-- PY 3.91
PJ PM 3.07
PE -- 3.23
-- PY 3.42
-- PZ 3.91
PJ PM 3.07
-- PR 3.23
-- PY 3.42 GS
PJ PM 3.07
PF PP 3.23
-- PY 3.42
-- PZ 3.91
Q10 QJO 2.93
QTO QAO 3.42
Q1 QJ 2.93
QT QA 3.42
NB RB Stage I & GS 2.93
NC RC Stage I 3.23

 

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