Following is an article about rear axle ratios.  This article was originally posted in the Forum.

I’m not into the 61 that much but the ratios were the 3.08, 3.23, and 3.36. I can give you the standard and optional axle ratios for 62 and 63 and I think 61 would be about the same even though 61 had a 3 speed Automatic.

Here is what I have for 62 Hydramatic
F-85 (except 117 and 167) standard was 3.23 with or without A/C, optional expressway ratio was 3.07 with or without A/C, and optional mountain ratio was 3.36.

F-85 (117 and 167) standard was 3.36 with or without A/C, optional expressway and mountain were N/A.

F-85 (15 ” wheels) standard was 3.36 with or without A/C, optional Expressway ratio was 3.23 with or without A/C, optional mountain ratio was N/A.

Here is what I have for 62 Syncromesh
F-85 (except 117 and 167) standard ratio was 3.07, optional expressway was N/A, optional mountain ratio was 3.36.

F-85 (117 and 167) standard ratio was 3.36, optional expressway was N/A, and optional mountain ratio was N/A.

F-85 (15″ wheels) standard was 3.23, optional expressway was 3.07, and optional mountain was 3.36. Now on the Jetfire I’m not sure but I think the standard ratio was 3.36.

Here is what I have for 63 Hydramatic
F-85 (except Cutlass) standard ratio was 3.23 with or without A/C, optional expressway ratio was 3.08 and optional mountain ratio was 3.36.

Cutlass and Jetfire standard ratio was 3.36 with or without A/C, optional expressway and mountain was N/A.

F-85 (15″ wheels) standard ratio was 3.36 with or without A/C, optional expressway was 3.23, and optional mountain was N/A.

Here is what I have for 4 speed syncromesh
F-85 (except Cutlass) standard ratio was 3.08, optional mountain ratio was 3.36, optional expressway ratio was N/A.

Cutlass and Jetfire standard ratio was 3.36, expressway and mountain ratio was N/A.

F-85 (15″ wheels) standard ratio was 3.23, optional expressway ratio was 3.08, and optional mountain ratio was 3.36.

Cutlass Coupe (15″ wheels) standard ratio was 3.36, optional expressway and mountain ratio was N/A.

Here is what I have for 3 speed syncromesh
F-85 (except Cutlass) standard ratio was 3.08, optional mountain ratio was 3.36, optional expressway ratio was N/A.

Cutlass and Jetfire standard ratio was 3.36, optional expressway and mountain ratio was N/A.

F-85 (15″ Wheels) standard ratio was 3.23, optional expressway ratio was 3.08, optional mountain ratio was 3.36.

Now this is what I have and as you know options could and most likely did change during the year so you could have a ratio that is different than what I listed. I would have to say that the 3.36 was the most common ratio with the 3.23 next.

I hope this helps you on ratios.
Bruce