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Home Blog Blog Rear axle ratios

Rear axle ratios

This topic contains 7 replies, has 1 voice, and was last updated by  62OF85conv 6 years, 5 months ago.

Viewing 8 posts - 1 through 8 (of 8 total)
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  • #7080

    62OF85conv
    Participant

    I would be curious what ratios are most common in the cars listed on this forum.

    My 61 shop manual refers to only 3 ratios being available: 3.08; 3.23 and 3.36. (My 62 Supplemental shop manual lists the same three).

    All 3 are listed as possible behind the hydramatic trans. But only the 3.08 and 3.36 are listed behind the synchromesh (doesnt say whether 3 or 4 speed manual tho).

    My car (with 4S hydramatic)has a 3.36 axle however the speedometer gear is for a 3.08 which puzzles me. Was the transmission changed sometime in the past or did Olds put the wrong gear in to make gas mileage seem better? lol

    At any rate. What was most the common ratio behind the 3 different transmissions, and did the options change for 61/62/63? What was the standard and what was optional?

    Should this kind of info be added to the registration list?

    #7083

    jetfireman
    Participant

    Let me try to answer the question about rear axle ratios.
    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 would also have to say that your transmission was changed at some point and they never changed the speedo gears or your rear end was changed and it was different than the original. I hope this helps you on ratios. Bruce

    #7085

    62OF85conv
    Participant

    Thats a lot of data to digest but well worth having. Thanks Bruce.

    I guess the guy who ordered up my Cutlass conv in Pittsburg figured there were enuf mountains in Pa to warrant a 3.36 – wait I think your text did say a 3.36 was standard for a 3167 model.

    I do wish I had a bit more maintainence history on my car tho. I guess a transmission swap might explain the incorrect speedometer gear match and why the housing was a lot cleaner than one would expect after 48 years.

    About the 15″ wheels. I keep seeing stuff in books but no one seems to have ever actually seen a set on any Olds or Buick??? Just for everyones information they are -NOT- the same as Pontiac Tempest/Lemans wheels (mores the pity for those of us who would like to swap). Tempests were 5 lug cars (I owned a new Lemans 62-71).

    #7095

    deucephaeton
    Participant

    My son’s Jetfire came with the 15 inch wheels. He has 7 wheels and three are the correct color for his car. My buddy that rescued this car from a salvage yard in 71 spotted 4 more wheels at the time and bought those also. Rob’s not planning on selling his extras just yet.

    Luck is at the intersection of planning and opportunity.

    #7254

    bcroe@juno.com
    Participant

    I also have seen a couple cars with 15″ wheels, and small hub
    only covers. What I never saw was 14″ rims. But I managed to
    get a set, to mount the first radial tires available. Long before
    small cars with 13″ rims were common. Bruce Roe

    #7255

    deucephaeton
    Participant

    14″ were available on F-85s and Cutlass models. The Jetfire at least in 62 were only 13 or 15.

    Luck is at the intersection of planning and opportunity.

    #7328

    Booster
    Participant

    Greetings,

    My car originally came with 14 inch wheels. Due to the car’s air-conditioning, 15 inch wheels were not offered. I have since installed 15 inch wheels from a 1963 Buick Special wagon. These wheels share the same part number.

    I do have a 3:90 gear set up that is meant for 1963 Skylark posi, but the Jetfire shares the same posi parts as the Skylark. I haven’t installed as I thought it may rev the engine too much. Also, being in this small town, it would be hard to find a mechanic and proper tools to install it.

    Take care

    #7329

    62OF85conv
    Participant

    Considering the price of gasoline is rising with no real end in
    sight, you may want to think long and hard about changing to a
    taller rear rather than a lower one.

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