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

how much gear wear is too much on a t18

Discussion in 'Intermediate CJ-5/6/7/8' started by iamgeer, May 18, 2004.

  1. May 18, 2004
    iamgeer

    iamgeer Member

    Calgary,...
    Joined:
    Jan 30, 2004
    Messages:
    226
    All,

    My next project is installing a t18. I took the cover off of my recently aquired t18a and found a little bit of a surprise. I took some pics. Here is the link to my main page:

    http://members.shaw.ca/bocadog/

    Click on the Jeep link to see the pics. First gear appears to have what I would call quite a bit of wear. What do you guys think? Does it need to be replaced? There are no teeth missing and the oil appears to be clean (no water). I have not totaly inspected it to see how much metal is in the bottom.

    Thanks,

    Karl
     
  2. May 18, 2004
    lynn

    lynn Time machine / Early CJ5 HR Rep Staff Member

    Huntingdon PA
    Joined:
    Sep 20, 2002
    Messages:
    3,437
    Karl, I'll assume you've picked up this T18... it's heavy! ~145 lbs dry...
    It's not something you want to install, then take back out in 3-6 months to fix.

    The teeth look a bit worn and rounded. Not uncommon for these big, heavy non-synchro-low trannies. Now is the time to take care of that. While it's out, replace that worn first gear as well as the input and output bearings. That way, when you do get it installed, there will be no question about the integrity of the tranny.
    HTH, good luck!
    Keep us posted!
     
  3. May 18, 2004
    iamgeer

    iamgeer Member

    Calgary,...
    Joined:
    Jan 30, 2004
    Messages:
    226
    Where is the best place to get a rebuild kit and new gears?
     
  4. May 18, 2004
    lynn

    lynn Time machine / Early CJ5 HR Rep Staff Member

    Huntingdon PA
    Joined:
    Sep 20, 2002
    Messages:
    3,437
  5. May 18, 2004
    nickmil

    nickmil In mothballs.

    Happy Valley, OR
    Joined:
    Sep 23, 2002
    Messages:
    12,529
    Try and find a good used one if possible. New they are pretty expensive. Should be replaced. The ends of the tooth don't bother me, you could knock the burrs off with a dremel and run it no problem. I've seen them run fine with 1/2 the tooth missing all the way around, although I would never put one together like that. The wear on the other end of the teeth is what bothers me. You can see where the gear is worn through the surface hardening. It will get worse and start flaking apart under load. It won't come apart, but will put metal slivers throughout the tranny, including your bearings which the slivers, or flakes if you like, will destroy in fairly quick fashion. Nickmil.
     
  6. May 18, 2004
    iamgeer

    iamgeer Member

    Calgary,...
    Joined:
    Jan 30, 2004
    Messages:
    226
    I did not even notice the surface wear. Thanks for pointing it out. From the tsm I think that I might have to replace the main shaft too. I dont know for sure yet though. I visited parts mikes website and he sells a first gear for 99 bucks. I think that this might not be such a good idea to replace only the first gear because it would mesh with an older gear with wear. One final question, does the wear pattern normal is does it indicate hard use?

    Karl
     
  7. May 18, 2004
    OKJeepin

    OKJeepin New Member

    Poteau, OK.
    Joined:
    Apr 16, 2004
    Messages:
    23
    From what I can tell it looks perfectly normal for a non-syncronized <(is that spelled right?) 1st gear tranny like the T-18a, we have put in a few in our Jeep club, and they all have looked like the pics you have, some a little worse, some better. We have never had any problems with the T-18a's at all because of this wear, but that could just be luck. A little impatient grinding into first gear before you come to a complete stop will slowly wear 'em out I guess.
     
  8. May 19, 2004
    nickmil

    nickmil In mothballs.

    Happy Valley, OR
    Joined:
    Sep 23, 2002
    Messages:
    12,529
    Should've mentioned to check the reverse idler gear also as that is the gear that meshes with the first gear slider on the actual tooth of the gear where you have the wear problem. It's common for the reverse idler to wear in the same fashion. They really both should be replaced IF the reverse idler shows similar wear. Also check for wear on the counter gear shaft, common to wear out. Check the inside of the first gear ring where it shifts over second gear also as this is another common wear point. Check the main shaft where the pilot goes into the input shaft, as they will sometimes where there also. If the pilot is worn, a good machine shop can retip it with a hardened sleeve. One other thing to check is the reverse spring in the shifter top. 9 out 10 of those are either broken or worn out. Nickmil.
     
  9. May 19, 2004
    iamgeer

    iamgeer Member

    Calgary,...
    Joined:
    Jan 30, 2004
    Messages:
    226
    Nickmil,

    I am getting the sense that you have seen you fair share of t18s. Thanks for all the info, I really appreciate it. The reverse idler does have some wear similar to first gear but not as extensive. I am hoping to have some time to tear into it this weekend and get a good look at the counter shaft. I will keep you posted.

    Karl
     
  10. May 19, 2004
    mb82

    mb82 I feel great!

    Charlottesville Va
    Joined:
    Mar 17, 2003
    Messages:
    2,706
    hey that looks like mine. my tranny guy said dont worry about it. i still will. if the tranny breaks i have a spair sitting under the house that is suposed to go into my dads future project.
    and one major thing i was told to look at. the input bearings, those most likely will need replaceing. not exactly sure why they get flatspots but they aparently do.
     
  11. May 20, 2004
    nickmil

    nickmil In mothballs.

    Happy Valley, OR
    Joined:
    Sep 23, 2002
    Messages:
    12,529
    That wear won't cause breakage. The surface hardening will continue to flake off and will run through all the bearings and ruin them. If it's a vehicle that doesn't get driven much then you can probably get away with it for a long time. If it sees a lot of drive time then it will wear out the bearings quickly. Of course if you hardly use first or reverse then it's not a problem as you aren't running on those gears then. I won't allow a tranny I rebuilt to go out the door like that unless it's a situation where parts are simply not available, but then I'm very picky and kind of anal retentive. I can attest that those tranny's are heavy. They weigh in at 157 lbs. dry with the top and shifter. I've worked on my share of them. ;) Probably rebuilt at least 2 or 300 of them in the last 10 years. Nickmil.
     
  12. May 24, 2004
    iamgeer

    iamgeer Member

    Calgary,...
    Joined:
    Jan 30, 2004
    Messages:
    226
  13. May 24, 2004
    iamgeer

    iamgeer Member

    Calgary,...
    Joined:
    Jan 30, 2004
    Messages:
    226
New Posts