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t 90 transmission

Discussion in 'Early CJ5 and CJ6 Tech' started by jasonjp62, Mar 21, 2013.

  1. jasonjp62

    jasonjp62 Member

    Ok guys school me a little here. I am tearing down the t90 that Stout gave me. the case has the typical t90 a1 on the side
    [​IMG]
    Now when I was pulling the front input off of it I noticed this
    [​IMG]
    It has the longer input on it as well.
    [​IMG]
    [​IMG]
    I really just needed the case to rebuild my t 90 but is this a t 86 or just hangover from older parts?
    And what do I look for to see if the parts inside is t 90 or t86?
    And here is why they pulled the tranny
    [​IMG]
    What would cause this kinda damage
     
  2. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    It's a T-90. The splines of a T-86 main shaft spiral, and the teeth on the T-86 1st and reverse are beveled. Straight splines and straight teeth is T-90.

    Input shaft looks long - maybe it's the T-90J input with a T-86 bearing retainer?
     
  3. jasonjp62

    jasonjp62 Member

    Thanks Tim, I was wondering because the gears and lower cluster looked allot like the t 90c and the second gear was the same. the input is way longer than the one from the 4cyl input. So I'm guessing what you said is right. the t86 markings just threw me off.

    thanks!
     
  4. Walt Couch

    Walt Couch sidehill Cordele, Ga. 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Pretty common to see T-86 input retainer and that will be the T-90J input shaft and as Tim said, all else in there is T-90. That blocking ring sure looks sad. Never seen one chewed that bad on a working tranny. Have no clew.
     
  5. jasonjp62

    jasonjp62 Member

    I messed around with it before I tore it down and it wouldn't go into 3rd gear. I have seen blocking rings with the teeth chewed off but never seen one like this before either. It would be really cool if these old things could tell their story of what happened.
     
  6. nickmil

    nickmil In mothballs.

    Usually caused by the input and pilot bearings being bad. I have seen them chewed up like that also when the 2-3 synchronizer inserts broke allowing the blocking ring to spin around inside the synchronizer assembly. The inserts breaking is common on T-90's.


    Sent from my iPhone
     
  7. Warloch

    Warloch Did you say Flattie??? Staff Member

    Yup - typical setup for a T90 converted to a V6.

    In addition to what Nick said, I have seen them like that when the needle bearing on the nose there were miss installed or mangled from the input issue.

    If you measure the T90C cluster against the T90A at the gear points, you will see the difference - notable in the diameter of the large gear on cluster and it's mate on the input shaft gear.
     
  8. Bob-The-CJ

    Bob-The-CJ Member

    I would guess the retaining pin from the shifter fell inside it. That or another piece of metal of similar shape. Just a guess but I had one do something also the same thing once upon a time
     
  9. jasonjp62

    jasonjp62 Member


    I noticed the difference in the one that was in the tranny and the one you sold me Warlock, the t90c cluster is probably 1/4" larger than the one in this tranny.
     
  10. jasonjp62

    jasonjp62 Member

    I have one more question. I was cleaning up some of the parts today, one of our members is interested in the input and retainer, From where the blocking ring got tore up there is brass on the input.

    My question is can the brass be removed without messing up the back of the input? or is the input trash at this point?

    [​IMG]
     
  11. Howard Eisenhauer

    Howard Eisenhauer Administrator Staff Member

    It it brass stuck to the surface or is the surface pitted with brass in the pits?

    if it's pitted it's junk, if it's stuck on the surface (& I don't understand how that could actually happen) then it's probable that the steel underneath has lost it's heat treatment for hardening- Either way I'd be looking for a new piece.

    H.
     
  12. duffer

    duffer Rodent Power

    Just out of curiosity, what does the inside race of the input look like? Like Howard, I wouldn't be using that.
     
  13. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    You have a wire brush in a bench grinder? It attack a part of the stuck-on bronze (maybe brass) with that and see what the steel underneath looks like.
     
  14. jasonjp62

    jasonjp62 Member

    Inside the race looks decent. I think what happened to this was, When I took it apart, I noticed there was a bearing laying flat in the in the front of the race. I think that's what started all the damage.

    I did just this and the bronze will not come off, and it's pitted, It's a shame that the input is junk.

    Thank you guys for the comments. Appreciate it!!
     
  15. Warloch

    Warloch Did you say Flattie??? Staff Member

    Jason - send them my way - I have several of those if they are looking for one.
     
  16. jasonjp62

    jasonjp62 Member

    Done, thanks Warloch