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Flathead 4-speed Transmission?

Discussion in 'The Hokey Ass Message Board' started by oldsboy, Feb 26, 2011.

  1. oldsboy
    Joined: Oct 24, 2005
    Posts: 510

    oldsboy
    Member

    Hey guys. I've tried to search the hamb for a few threads related to some information on these but the fact that I can't find anything is making me not feel to positive about now having one.

    I've recently purchased a 40 ford top shift trans thinking I would use it for my current build (model T sedan early 40' style) with a 59 series flathead but realized its a 4 speed rather than a three speed. Is this a big mistake? Has anyone used the 4 speed for a hot rod. I don't recall ever seeing one but I haven't been around all that long. Should I start looking for a non-4 speed and look for a three speed and just ditch this one? I need some help here fellas, how deep of trouble am I in???
     
  2. mtflat
    Joined: Jan 28, 2003
    Posts: 422

    mtflat
    Member

    It depends which 4 spd - there were two. One, the most common truck trans, has straight cut gears with granny low. The other was used behind the big six and it has bevel gears on 2,3 and 4. 1 and R are straight cut.

    The truck style will need to be double clutched and will never be a fast shifting trans. Then again the 3 spd HD truck trans isn't very fast either.

    If you want to learn to shift without the clutch, feathering the gears and learning to adjust your rpms you'll have a theft-proof transmission that kids can't steal. If you want to get on the accel pedal and go thru the gears, you'll probably do better with a car or light duty truck 3 spd.
     
  3. oldsboy
    Joined: Oct 24, 2005
    Posts: 510

    oldsboy
    Member

    Alright, so it sounds like I should avoid the 40 trans I just picked up....unless someone can issue an alternative.

    So any thoughts of the following scenarios?

    1. I find a light truck trans or find a car 3 speed and go that route staying traditional.

    2. I do have a good world class t5 out of a camaro that I could use but I would need do the s10 tailshaft swap and pick up a flathead adapter

    Any clues as to which would be a better way of doing things? would it be more economical to do the tailshaft swap or going the traditional route.

    3. What do I do with the 40 truck 4 speed?
     
  4. Barry-Ct.
    Joined: Jan 16, 2011
    Posts: 6

    Barry-Ct.
    Member

    THe 40 4 spd is pretty much a boat anchor. THe light duty truck 3 speed is a good bet if you want to stay traditional. THe t-5 is a good swap if you want to shift fast. Alot of people go that route.

    Barry

    50 F-1
     

  5. barry wny
    Joined: Dec 31, 2009
    Posts: 451

    barry wny
    Member

    If you are using a banjo the easiest is to use the transverse spring torque tube & regular trans, top loader case is hard to come by, column shift is easy to find. The " '39 trans" hype i don't get, my earlier trans works good, and paid $5 for a spare top shift at an auction with '36 numbers. When it's coupled up and right, priceless
     

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  6. oldsboy
    Joined: Oct 24, 2005
    Posts: 510

    oldsboy
    Member

    I am using a banjo rear. SO it would just be, it sounds like, a Whole lot simpler to find a top shift trans? would a side shift work or is top shift preferable now?

    Sorry for all the questions but, I'd rather have the answers than sit and question myself. THanks for the help so far guys.

    If anyone wants to check out my build thread go here:
    http://www.jalopyjournal.com/forum/showthread.php?t=549465&highlight=oldsboy
     
  7. This a long time ago but I thought the old circle track guys used truck four speeds and some how changed the gearing inside the transmission. They may have eliminated one gear or something. Mybe I was having a strange dream too.
     
  8. chopt top kid
    Joined: Oct 13, 2009
    Posts: 959

    chopt top kid
    Member

    If you want the desirable "39 tranny", find a good 78 series gearbox, and load it with '41-'48 passenger car gears from a side shift transmission. The 78 series gearbox is found in the '37-'39 passenger cars and the '37-'51 ford pickups. Although Ford's improved gearset was introduced in the '39, it was not all inclusive until the '41 model year... Check Vanpelts website...

    If you want to run 70-75 mph on the freeway, get yourself a T5 from a V8 Camaro with the 2.95 1st and the 0.73 5th. Install a S10 tailshaft and do an open drive conversion with a torque arm. Check out Flat Ernie's T-5 Tech for info on the T-5 Hybrid. Check Hot Rod Works for open drive conversions and good idea's on a torque arm...
     
    Last edited: Feb 26, 2011
  9. Hoop-in-JAX
    Joined: Nov 7, 2007
    Posts: 184

    Hoop-in-JAX
    Member

    You must keep in mind that all the advice you get may not be 100% correct, and that you must educate yourself and be able to identify the differences in the various years.

    For example, if you choose to build a "39 transmission" from canabalized parts, there were at least 5 different gear ratios available in the early 40's. ( ... and the teeth do not always add up to 44.)

    Do a lot of searches and reading ... everything on Mac Van Pelt's site for openers, including his parts lists and pricing. Also, this site: http://www.btc-bci.com/~billben/trans.htm

    You should be able to recognize the late blocker synchros used in the '39 by a quick glance into the case. And, you do have to look inside and not rely on the design of the .....

    ... shifter top. Another requirement so far not mentioned. Check Mac VP's site and be familiar with the tops, but understand the design was also used/modified for use with "pre-39" gears. And, that earlier tops could have the required 3' fork with late gears inside.

    Finally, if you do have to spend some extra money to get a good transmission, it's nice to know that they ARE popular and that the prices are not going down.
     
  10. barry wny
    Joined: Dec 31, 2009
    Posts: 451

    barry wny
    Member

    Any of the transmissions will fit, the rear bearing retainer/mount/tube connectors come in different configurations but interchange. You will find a column shift car transmission easiest & cheaper, I would grab the first one I could find to fill the space for now. I used an empty side shift to mount everything, shorten the torqtube, build park brake, pedals etc... Then ran across a 46 car trans cheap, used the gears in a early top shift case & had a 49 truck top piece. I did not use instructions, but understand the popular "K" member uses a rubber donut type end piece, the important thing is all the later mounts are a couple of inches narrower & further back. So if you use a later x member ( as opposed to the hard to find expensive k member) like I did, need to position it with the later mount in mind. Check this link:
    http://macsautoparts.com/search.asp?sb=0&ls=y&camid=F30&year=0&make=&ss=Transmission&x=21&y=7
    About 5 rows down shows some mounts
    I have at least 4 empty side shift cases, if closer you could have one for mock-up, basicly scrap otherwise. Also the top loader has the clutch lever on the trans shaft, it was easier for me to use the bell crank & frame mount pivot & make the pedal link work.
     
  11. oldsboy
    Joined: Oct 24, 2005
    Posts: 510

    oldsboy
    Member

    Thanks for all the info guys. I've been trying to do as much reading on these as I can. I've picked up the vern tardel "let me help you series" and the bible of hot rodding the how to build a traditional ford hot rod" both of which have helped quite a bit. Along with all the good tech info here on the hamb.

    I've actually just located a '37 for a very decent price that I may move on. Any last words or thoughts? Thanks again for all the help.
     
  12. chopt top kid
    Joined: Oct 13, 2009
    Posts: 959

    chopt top kid
    Member

    I would check the series number to see if it is in fact a 78 series box, or a left over 48 series. Henry had a habit of using all of the left over parts on the following model year. The number is located on the rear of the case beneath the tailshaft and is usually covered up by greasy dirt. Good luck...
     
  13. Hoop-in-JAX
    Joined: Nov 7, 2007
    Posts: 184

    Hoop-in-JAX
    Member

    "I would check the series number to see if it is in fact a 78 series box, or a left over 48 series."

    Are you saying he should not use a 48- case?
     
  14. bloodyjack
    Joined: Aug 29, 2007
    Posts: 649

    bloodyjack
    Member

    the truck 4 speed comes with a hogshead that you can use as a T5 adapter
    with Dwight Bonds piece. Like this

    [​IMG]
     
    Last edited: Feb 28, 2011
  15. oldsboy
    Joined: Oct 24, 2005
    Posts: 510

    oldsboy
    Member

    Yeah I'm having the guy fellow check to see if it is a 78 before I go ahead with it

    Unfortunately I believe its off a 40 heavy duty so the "hogshead" is actually cast onto the rest of the case and is not removeable...
     
  16. JF
    Joined: May 15, 2008
    Posts: 519

    JF
    Member
    from Utah

    I dont know from experience (yet) but if using a flathead and a T-5 trans why not just use a T-5 from an S10 to begin with instead of going to the hassle of swapping the tailshaft and getting the speedo gears to line up etc? I don't know how much HP and torque the S10's put out but I can't imagine it being more or much more than the flathead?? probably more torque if anything


    by the way, thats the route I'm going with my 51 F1 (rebuilt 49 Merc flathead with S10 t5 trans using the 4 speed hogshead and dwight bonds adaptor). just need to start assembling everything ...


    Cheers and good luck
     
  17. Ford Guy
    Joined: Jan 9, 2010
    Posts: 53

    Ford Guy
    Member

    I just put a t-10 into my F1 and have a HD 3 speed floorshift I would sell if the offer is right. Don't know what they're worth though. Anybody got any pricing info?
     
  18. Mr48chev
    Joined: Dec 28, 2007
    Posts: 33,931

    Mr48chev
    ALLIANCE MEMBER

    The Hogs Heads were/are on/with the later truck 4 speeds. I just picked a 46 transmission and hogs head up a couple of weeks ago to put behind the 254 six in my boat tail. I didn't really care if I had a bit of slow shifting as the price was right and the the trans will work with the clutch pieces I already have. The Vanpeldt site has the trans ID info that is needed for finding out what you have though.
     
  19. Sturgis39, Your dreams are real close to what we used. Some guys would use a Muncie 4 speed and only use 3/4 gears. They would cut off the 1st and 2nd gear teeth to reduce drag. I used a 57Chevy p/u 3spd trans and used 2/3 on the track. I only used 1st gear to pull onto the trailer. That trans held up behind a 500 hp Chevy 366 SB. I carried a spare for 5 years and never had to use it......LOL
     
  20. oldsboy
    Joined: Oct 24, 2005
    Posts: 510

    oldsboy
    Member

    Alright, so I thought I'd post and update where everything sits. After the Lincoln swap meet this weekend I ended up with this little treasure. I actually stumbled across an original untouched '39 trans great condition. I think I'm happy.

    [​IMG]

    [​IMG]

    [​IMG]

    Thanks for all your help and information guys. I think this is the best way to go for the build...
     
  21. hasty
    Joined: Jul 5, 2009
    Posts: 1,411

    hasty
    Member

    Nice score. Hope it works out
     

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