What do I have??

Discussion in 'VIN, Trim Tag & Drivetrain Decoding' started by TX79Z28, Jun 27, 2014.

  1. Gary S

    Gary S Administrator Lifetime Gold Member

    Messages:
    23,926
    Likes Received:
    1,513
    Joined:
    Apr 14, 1999
    Location:
    Bismarck, North Dakota
    You can check the gear ratio by rolling the ring gear until you can read the numbers stamped on it. It should say 41 12 if it is a 3.42. If you divide 41/12, you get 3.42. If there are different numbers, simply divide the numbers, you get the ratio.
     
  2. 2ndGenCrazy

    2ndGenCrazy Veteran Member

    Messages:
    819
    Likes Received:
    54
    Joined:
    Aug 18, 2011
    Location:
    Upstate New York
    If you rotate the ring gear, there should be a series of stamped numbers including a date code, and number of teeth for ring and pinion.:crazy:
     
  3. TX79Z28

    TX79Z28 Veteran Member Lifetime Gold Member

    Messages:
    1,136
    Likes Received:
    0
    Joined:
    May 3, 2007
    Location:
    San Antonio, TX
    I did, but I cant make out the number, this is it:

    [​IMG]
     
  4. Gary S

    Gary S Administrator Lifetime Gold Member

    Messages:
    23,926
    Likes Received:
    1,513
    Joined:
    Apr 14, 1999
    Location:
    Bismarck, North Dakota
    Those cast numbers aren't the ratio numbers. You want the stamped numbers on the edge of the ring gear itself. If the ring and pinion are original GM, the ratio is stamped there.
     
  5. TX79Z28

    TX79Z28 Veteran Member Lifetime Gold Member

    Messages:
    1,136
    Likes Received:
    0
    Joined:
    May 3, 2007
    Location:
    San Antonio, TX
    Ok stupid question. Ring gear, that's the one with the actual teeth more or less on the left hand side of the pic?
     
  6. 1979CamaroTX

    1979CamaroTX Veteran Member

    Messages:
    178
    Likes Received:
    0
    Joined:
    Oct 10, 2006
    Location:
    Longview, TX
    Yes
     
  7. Gary S

    Gary S Administrator Lifetime Gold Member

    Messages:
    23,926
    Likes Received:
    1,513
    Joined:
    Apr 14, 1999
    Location:
    Bismarck, North Dakota
    Correct. It is the big gear shown on the left side of your first picture you posted. The numbers are stamped into the grooved part shown on the left side of your picture.
     

Share This Page