Need help to decode Saginaw 4 speed transmission

Discussion in '1947-1954' started by Blueflame236, Dec 15, 2012.

  1. Blueflame236

    Blueflame236 Member

    Joined:
    Mar 29, 2008
    Messages:
    1,555
    Location:
    Norway
    Hey guys

    I could need some help to decode this tranmission. The seller told me it whas in a 1968 Camaro ?

    What i have is;
    Saginaw 4 speed 2 grooves ; 1st. 3.11 sec. 2.20 Third 1.47 fourth 1.00
    Transmission block casting number R 7 T 28
    GM number 3890564

    Martinius.
     
    Last edited: Dec 16, 2012
  2. coilover

    coilover Member

    Joined:
    Mar 30, 2005
    Messages:
    2,491
    Location:
    Plano US
    Martinius,
    Contact Firewheels Classics in Wylie, Texas. Very nice people that get all our Camaro/Firebird/TransAm parts business. They know them forwards and backwards. www.firewheelclassics.com 1-800-711-0125 or just google firewheel classics Wylie, Texas.
     
  3. vwnate1

    vwnate1 Member

    Joined:
    Jan 1, 2000
    Messages:
    11,172
    Location:
    AMERICA !
    Sorry Martinus

    But I only know they made and used this fine tranny for decades and they're dead simple to overhaul , often not needing any new parts , just a good cleaning then mix and match parts from the old tranny .

    I had to do this on a 197? Camaro junker my buddy got cheated on , I told him to go get a guaranteed one from the local scrapyard and I'd do what I could ~ naturally they sold hi one that had totally different shifter , tail shaft housing and so on so I laid out some clean cardboard and took both apart in his upholstery shop then cleaned all the various bits , chose the best of the lot then re - assembled it and Lo ! GM & Saginaw's terrific basic design did the rest , it didn't leak and shifted great , no nose in second gear etc....... I re assembled the left over parts carefully so we got the core charge back without hassles .
     
  4. Blueflame236

    Blueflame236 Member

    Joined:
    Mar 29, 2008
    Messages:
    1,555
    Location:
    Norway
    Saginaw tranny!

    Nate

    I want to replace the other 4 speed in my truck as i am still not 100% content with it . It shifts very smoothly in all gears but in third and fourth gear there apears a lug sound when driving , wich i have not been able to identify where comes from ? The tranny i have bought a few weeks ago is in amazing good condition with no signs of wear at all. I will only replace parts if needed like synchros , o-rings ect. Noticed that the reverse idler gear is a bit smaller but the gear is bigger then the others i have seen , probebly because its a newer version og the Saginaw ?

    Alllmost identified the tranny but i am still questioning about the year the tranny whas made ?

    R 7 T 28

    R = Saginaw
    7 =
    T = december
    28= 28

    Martinius.
    ----------------------------------------------------------------------------------------------------------------------------------------------
    1967-1969 Camaro Transmission Code Format
    (except TH400 and B-W 3-speed)



    Trans Code Format: tymdds

    where:
    t = transmission type

    MANUAL AUTOMATIC
    S = Saginaw 3-speed A = 68/69 L6 Torque-Drive
    K = McKinnon 3-speed C = Cleveland Powerglide
    H = 69 Muncie HD 3-speed T = Toledo Powerglide
    R = 4-speed Saginaw B = Cleveland TH350
    P = 4-speed Muncie X = Cleveland TH350
    Y = Toledo TH350

    y = model year (not calendar year)
    m = month
    Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
    --- --- --- --- --- --- --- --- --- --- --- ---
    A B C D E H K M P R S T

    dd = day of month
    s = suffix
    PowerGlide and TH350 (not used on all):
    D = day shift
    N = night shift
    1969 Muncie 3-speed
    B = 2.42 first gear ratio
    1969 Muncie 4-speed only:
    A = M20
    B = M21 Use of the Muncie type suffix
    C = M22 began with 21 Oct 68 production.

    Examples:

    R7S21 Saginaw 4-speed, Nov 21, 1966
    P8R01 Muncie M2x 4-speed, Oct 01, 1967
    P9T11B Muncie M21 4-speed, Dec 11, 1968
    C9D14N PowerGlide M35 2-speed auto,
    Apr 14, 1969, night shift






     
    Last edited: Dec 18, 2012
  5. vwnate1

    vwnate1 Member

    Joined:
    Jan 1, 2000
    Messages:
    11,172
    Location:
    AMERICA !
    Saginaw Trannies

    Wow ;

    FIVE DAYS and no one here knows ths stuff ? :confused: .

    I'm feeling very sorry & useless right now as I can overhaul it in my sleep but I am stymied as to helping you Martinus .

    Sorry .
     
  6. Blueflame236

    Blueflame236 Member

    Joined:
    Mar 29, 2008
    Messages:
    1,555
    Location:
    Norway
    Transmission trouble shooting?

    Thanks fore your reply Nate.

    After i opened the late modell Saginaw tranny today ( 68 camaro ) i`ll noticed that all the gears are build in a better way then the earlyer models. All are helicoil cut except from the straight teeth reverse gear .The idler shaft has a stop to keep the gear in an excact position so it wont scrub the inner house sidewall when it returns back.

    Martinius.
     
    Last edited: Dec 22, 2012

Share This Page