1. Registration trouble? Please use the "Contact Us" link at the bottom right corner of the page and your issue will be resolved.
    Dismiss Notice

T98 Help

Discussion in 'Early CJ5 and CJ6 Tech' started by Jay's WWII Jeeps, Dec 15, 2019.

  1. Dec 15, 2019
    Jay's WWII Jeeps

    Jay's WWII Jeeps Member

    Napa CA
    Joined:
    Mar 14, 2018
    Messages:
    54
    I have a CJ5 with the factory t98, vin checks out for it. The F head has been swapped to a SBC. In front of the t98 there is what looks to be the factory 7/8" steel plate then a aluminum adaptor that is about 3" long. FSJ input? Was this a common practice? Can I replace the input shaft with a short Ford style?
    I'm going to be using this behind a Kubota if it works out.
    Thanks
    Jay
     
  2. Dec 16, 2019
    48cj2a

    48cj2a http://bantamt3c.com

    Central Illinois
    Joined:
    May 4, 2003
    Messages:
    441
    I republished/hosted "Oldtimes" T98A info since photobucket made his images unavailable - good info

    http://48cj2a.com/T98A.htm

    [​IMG]
     
  3. Dec 16, 2019
    Jay's WWII Jeeps

    Jay's WWII Jeeps Member

    Napa CA
    Joined:
    Mar 14, 2018
    Messages:
    54
    That looks like the front and rear plate that I have.
     
  4. Dec 16, 2019
    timgr

    timgr Jeepin' Nerd 2020 Sponsor 2019 Sponsor

    Medford Mass USA
    Joined:
    Aug 10, 2003
    Messages:
    20,439
    Hard to be certain where they got the length for the extra adapter. Checked the parts book and it only shows the T-18 with a V8, including the 327. 230-only for the T-98, and there's no need for a long shaft with an inline 6.

    Online sources claim eht 327/T-98 combo appeared in J-trucks, but no corroboration by the factory documents.
     
    Last edited: Dec 16, 2019
    Jay's WWII Jeeps likes this.
  5. Dec 16, 2019
    Jay's WWII Jeeps

    Jay's WWII Jeeps Member

    Napa CA
    Joined:
    Mar 14, 2018
    Messages:
    54
    From what I can find on Novak is that it was also used in the 5/4 ton jeep truck of early 1970’s and Ford also used it in tricks. Was hoping that a ford input shaft could be an easy swap. As for bellhouse and stick out length Novak also claims that it’s the same between SBC and SBF just different bolt pattern.
    Thanks
    Jay
     
  6. Dec 16, 2019
    timgr

    timgr Jeepin' Nerd 2020 Sponsor 2019 Sponsor

    Medford Mass USA
    Joined:
    Aug 10, 2003
    Messages:
    20,439
    I don't see much help there. The 5/4 ton trucks came with the 230 OHC six, so they'd be set up like the '62-65 J-trucks that got the same 230/T-98 combo except with the Dana 20 transfer case. The shape of the J-truck and Wagoneer engine bay requires that a V8 be moved forward to clear the firewall while keeping the existing transmission placement. The sixes fit in the existing recess in the firewall, so no extra-long input needed. IIRC the 226 and 230 bells are the same, but I don't know what their depth is.

    Yeah, the Chevy and Ford bells are the same depth. Ken (oldtime) might know something about the Ford T-98 input. If you search old posts it might have come up before.

    Glad to help!
     
  7. Feb 5, 2020
    Jay's WWII Jeeps

    Jay's WWII Jeeps Member

    Napa CA
    Joined:
    Mar 14, 2018
    Messages:
    54
  8. Feb 5, 2020
    Jay's WWII Jeeps

    Jay's WWII Jeeps Member

    Napa CA
    Joined:
    Mar 14, 2018
    Messages:
    54
  9. Feb 5, 2020
    Jay's WWII Jeeps

    Jay's WWII Jeeps Member

    Napa CA
    Joined:
    Mar 14, 2018
    Messages:
    54
  10. Feb 5, 2020
    Jay's WWII Jeeps

    Jay's WWII Jeeps Member

    Napa CA
    Joined:
    Mar 14, 2018
    Messages:
    54
    I picked this up the other day, but don’t have it home yet. Any ideas on what this may be out of originally?
    Thanks
    Jay

    upload_2020-2-5_16-57-58.jpeg
     
  11. Feb 6, 2020
    oldtime

    oldtime oldtime

    St. Charles,...
    Joined:
    Aug 14, 2006
    Messages:
    2,707
    Certainly an early Jeep T98 it's from the Willys 1956-1962 or the Kaiser era 1962-1971.
    It has a GM pattern aluminum adapter plate.
    It has a typical Jeep small hole D18 transfer case.

    There are two unusual things that I notice.
    The TC high / low shift lever has a foreward bend to it.
    The T98 shift cane looks to be rather short and not well tapered toward the threaded end. (however the photo may be misleading)

    The MDG looks too long and fat to be the 15/16" CJ version.
    In the pic it looks a lot like the M715 MDG.
    But most all of of the other parts do not match with M715.
    What is the MDG diameter and stickout length as measured from the front transmission face ?
     
  12. Feb 6, 2020
    Jay's WWII Jeeps

    Jay's WWII Jeeps Member

    Napa CA
    Joined:
    Mar 14, 2018
    Messages:
    54

    I will be able to measure that next Tuesday with any luck. I think the same as you an early cj that has had the input shaft changed to a 5/4 truck and then adapted to sbc.
    Thanks
    Jay
     
  13. Feb 6, 2020
    timgr

    timgr Jeepin' Nerd 2020 Sponsor 2019 Sponsor

    Medford Mass USA
    Joined:
    Aug 10, 2003
    Messages:
    20,439
    The M715 drivetrain resembles the pre-66 230 OHC trucks, except for the divorced transfer case of the M715. They came with the Dana 20. They were also optionally equipped with the T-98. I don't know how much the stickout for the 230 was, but it would be shorter than the V8s - no need to move the engine forward to clear the firewall.

    Seems more likely it's from a 230 J-truck that was adapted to a Chevy or other GM engine. Even in the early '70s, these trucks (and Wagoneers) were cheap and many were adapted to small block V8s. Shifter is wrong for that though ... could also be from a Utility truck with a T-98 - I expect the shifters are right for that.

    Tag numbers?
     
    Last edited: Feb 6, 2020
  14. Feb 6, 2020
    oldtime

    oldtime oldtime

    St. Charles,...
    Joined:
    Aug 14, 2006
    Messages:
    2,707
    Unless it's a mix/match of component it's certainly not from an M715 excepting perhaps the MDG itself.
    Yes not sure if I have info on this but it surely may be from a Jeep PU that had the Hemi 230 "Tornado" engine. (1962-1973)
    In fact that seems highly likely to me without checking into it.
     
  15. Feb 6, 2020
    Jay's WWII Jeeps

    Jay's WWII Jeeps Member

    Napa CA
    Joined:
    Mar 14, 2018
    Messages:
    54
    We will know more by Tuesday!!! Hopefully I can find the parts to make mate to a ford or Chevy with out the alum spacer.
    Thanks again
    Jay
     
  16. Feb 7, 2020
    oldtime

    oldtime oldtime

    St. Charles,...
    Joined:
    Aug 14, 2006
    Messages:
    2,707
    Looks like prior to the Jeep T18, Jeep only used 2 different maindrive gears with the T98.
    Of course there was the short 15/16" diameter MDG that the 4 clyinder CJ used 1956-1971.
    Jeep part # 912361 is 10-3/8" OAL. (of course the stickout from front of transmission is 2-5/8" less than the OAL)

    Then there was the 1-1/8" diameter MDG that was used behind FC 170 with 226 from 1958-1964.
    There was also the exact same MDG that was used with all T98 / 230 Tornado applications.
    This includes the 1963-1964 Gladiators (To the best of my knowledge they were not available for Wagoneers) and the 1967-1968 M715's.
    Jeep part # 916341 is 12-7/8" OAL. (of course the stickout from front of transmission is 2-5/8" less than the OAL)

    Sorry no info the 1965/1966 FSJ's with 327's but I expect Jeep essentially went exclusively to T18 after that time excepting the M715 trucks and 4 cylinder CJ's.

    So the T98 in your pic is almost certainly from a 1963 or 1964 Gladiator because the earlier FC was remote shift.
     
    Jay's WWII Jeeps likes this.
  17. Feb 8, 2020
    Jay's WWII Jeeps

    Jay's WWII Jeeps Member

    Napa CA
    Joined:
    Mar 14, 2018
    Messages:
    54
    Old time,
    Does this mean that I should be able to turn down existing MDG to sbc specs and ditch the alum adaptor? That would give me 2.5” of drive shaft length.
    Thanks
    Jy
     
  18. Feb 8, 2020
    oldtime

    oldtime oldtime

    St. Charles,...
    Joined:
    Aug 14, 2006
    Messages:
    2,707
    Yes I believe you could shorten the longer 1-1/8" T98 MDG to make it fit more direct to an older GM engine.
    I hear Moser does a good job with re-splining etc.
    But of course that will most likely remove part of the case hardening from the pilot tip.
    Not sure how critical that hardness actually is???
    Ask Moser and let us know...
    Do not try to use a T18 MDG since it has the wrong mainshaft pilot bore diameter etc.

    On T18's I eliminate all front adapter plates via welding new ears onto an otherwise standard Jeep T18 case.
    Then I install a short 1-1/16" Jeep maindrive gear.
    That allows it to fit the Dauntless without extra unwanted length.
    Never tried it with a Jeep T98 but see no reason it can't work just as well.

    One good thing about 1-1/8" MDG is that it's the standard diameter for older GM engines.
    Was also a standard diameter for many Jeep applications.
     
    Jay's WWII Jeeps likes this.
  19. Feb 8, 2020
    oldtime

    oldtime oldtime

    St. Charles,...
    Joined:
    Aug 14, 2006
    Messages:
    2,707
    I'm guessing you could consider using use a 6-1/2" Ford T98 MDG which is nearly "too short" for GM bellhousings.
    I believe the Ford version would be 1-3/8" diameter and not certain if it it will match the Jeep pilot bore.
    All T98 transmissions will have the 6.40 ratio.
     
    Jay's WWII Jeeps likes this.
  20. Feb 8, 2020
    Jay's WWII Jeeps

    Jay's WWII Jeeps Member

    Napa CA
    Joined:
    Mar 14, 2018
    Messages:
    54
    It would be nice to use a factory part. Do you know the part number for the MDG? Why do you say too short? Novak has both gm and ford at 6.5” stick out.
    Thanks
    Jay
     

Share This Page

New Posts