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

t18 and dana 20

Discussion in 'Early CJ5 and CJ6 Tech' started by piffey263, Oct 4, 2013.

  1. Oct 4, 2013
    piffey263

    piffey263 Active Member

    Medford, OR
    Joined:
    Oct 16, 2008
    Messages:
    1,214
    I picked up the holy grail for a later model cj5...but have a early cj5

    I got a t18 that was out of a 77 cj5 with the granny low, that has an aluminium adapter to a dana 20 with terralow gears 4:1. which was bolted to a AMC 304...(i got the bellhousing and clutch too)


    I got a couple questions here?

    first what should I do with this stuff,

    I would like to use it in my jeep, which has a buick 225, t14, dana 18, and a tapered rear axle.

    these are the option I came up with
    A:swap the dana 20 adapter and case to ford t18
    B:use novak's amc to gm trans adapter
    C:shock:ther?

    next is it possible to convert this dana 20 case to side output? while retaining the dana 20 gears?
    I know you can swap the dana 18 guts with a bronco 20 part but haven't found anything about the other way.
    Or should I run the 20 case as is?

    or turn around and sell it to someone else who can just install this minimum effort in there late cj5
     
  2. Oct 4, 2013
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Medford Mass USA
    Joined:
    Aug 10, 2003
    Messages:
    23,596
    Nick will know better, but the main issue I have with this - I have no idea what the bell and stickout is for the HG T-18. I know it will bolt up to the AMC engines, but I suspect you can't use any of it to adapt to a GM bell - without an expensive GM-to-AMC adapter.

    The main value to you is the T-TC adapter and T-18 main shaft. The rest of it is not really useful.

    Why wouldn't you run your existing Dana 18? The Dana 20 pattern is the same, and you will need a 6-spline output gear for your existing transfer case. Not much value in the Dana 20 with an offset rear axle, unless you need a new case. You can use the somewhat heavier Dana 20 case and put all the Dana 18 gears inside, but it's probably not worth it unless you are upgrading with Tera gears or such. The Dana 18 gears in the Dana 20 give you the better low range of the Dana 18 in a Dana 20... you already have the better low range.

    Likely your best option is to flip it to an intermediate or late CJ owner.
     
    Last edited: Oct 4, 2013
  3. Oct 4, 2013
    djbutler

    djbutler Sponsor

    Rio Linda CA
    Joined:
    Nov 5, 2007
    Messages:
    727
    Piffey,
    I thought about jumping on this one too when I saw it on CL, but funds are short.
    If I were you I would look for a Ford T18, and use the Jeep T18 mainshaft and adapter. Do the same thing as Wheelie's T-18 build thread in the fabricators forum, except with your Jeep T18.
    On the transfer case, use the rear output housing from your D18 on the D20, convert it to the D18 configuration. This should keep the Terra-low gears.
    You should wind up with a T18 that will fit up to your V6 bellhousing, a factory adapter to the transfer case setup as a D18 configuration with super low range from the terra-low gears.

    Don
     
  4. Oct 4, 2013
    piffey263

    piffey263 Active Member

    Medford, OR
    Joined:
    Oct 16, 2008
    Messages:
    1,214
    either way, I can't do anything to this set up right away. So I got plenty of time to figure out the best option and will probably go back and forth between the options.

    The adapter has AA on it so I assume advance adapters not sure if this would change things or not..


    timgr: I would run the dana 18 without question because my offset axle but this new dana 20 has 3.15 teraflex gears. Hence why i'm thinking about going the opposite way of normal people... I know 2.43 to 3.15 isn't much but would like to leave axle ratio at 3.73 and get lower gears.

    According to Novak, the stick out should be 7.43. this doesn't mean anything to me at moment. I will keep reading



    Don: this was what I was hoping when I bought it, is to swap the guts to a ford case as what wheelie was doing.

    the converting the dana 20 case to dana 18 while utilizing dana 20 gears is what i'm having trouble finding. I think I will have to sit down and look at some diagrams.
    at least I got the large hole dana 18 case so if it is possible i'm in right direction.



    Possible ways of doing this..
    $218 Novak adapter Gm bell housing to AMC t-18 but its half inch thick.. I'm worried about length
    http://www.novak-adapt.com/catalog/adapters/engine_to_transmission/kit_1879.htm

    R&p wants 249 for a ford case and then swap the guts
    http://shop.rp4wd.com/product/red-transfer-case
    At some point I could and probably should call them because I know not all there products are listed

    pick one up ford trans at pick and pull/craigslist and do necessary machine work and utilize AA adapter and dana 20 gears.
    around $54 for front bearing retainer at novak
     
  5. Oct 4, 2013
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Medford Mass USA
    Joined:
    Aug 10, 2003
    Messages:
    23,596
    Yes, the AA adapter would change everything. It means it's not Jeep. See if you can find any numbers on the adapter. The '77-79 CJ T-18 is all Jeep, front to back. If it's a converted transmission, it's probably Ford with a T-150/T-176 bell. That's the usual way if you are going to use an aftermarket T-TC adapter. You can also post numbers from any tags... a Jeep T-18 will have a tag under the top cover bolt. Pics... Pics...

    I kinda doubt that the 3.15:1 gears from a D20 will work in a D18. The gears would be easy to part out and sell, or sell the D20 alone. Nick might know, or call TeraFlex and ask them. If you are going to call R&P, they could tell you about the gears.
     
  6. Oct 4, 2013
    piffey263

    piffey263 Active Member

    Medford, OR
    Joined:
    Oct 16, 2008
    Messages:
    1,214
    cover
    [​IMG]

    Case
    [​IMG]

    AA adapter: need better picture of number just realized where the number was
    [​IMG]

    Edit
    [​IMG]
    Dana 20 case
    [​IMG]
     
    Last edited: Oct 4, 2013
  7. Oct 4, 2013
    piffey263

    piffey263 Active Member

    Medford, OR
    Joined:
    Oct 16, 2008
    Messages:
    1,214
    1301065907 I'm coming up with a Ford transmission....I hope this is correct.. I know you can't go by the numbers as been stated before.
    I'm not pulling anything on the AA adapter yet.
     
  8. Oct 4, 2013
    tarry99

    tarry99 Member

    Northern California
    Joined:
    Oct 29, 2012
    Messages:
    3,784

    Piffey...............I think your still in great shape..............first off that is a Borg-Warner Ford case #1301-065-907 and the shifter # 13-01 097-906 looks to be a late shifter with I'm guessing 3 aluminum forks inside?.....shift pattern for reverse would be over and down........The input shaft stick out should be 6.5" from the front of the case.......You don't need an adapter between the Stock manual Buick Bell Housing.........If you look at that tranny case there are two extra boose's that are probably un-drilled on the face that you will need to use in order to get that attached to the stock Buick Bell housing. You would also change two hole locations in the bell housing be welding a piece of aluminum inside and threading it.........the two top holes in the Tranny also case need to be elongated to fit two that are already in the bell housing..............all common stuff been done hundreds of times.
    On the transfer case I do believe there is a solution to use the 3:15 gear in an offset drive application ...........but not sure without the right gear whether or not a Warn OD would work.................That is a NickMil question.........More pictures would be great! Good find!
     
  9. Oct 4, 2013
    piffey263

    piffey263 Active Member

    Medford, OR
    Joined:
    Oct 16, 2008
    Messages:
    1,214
    it has three bosses on right side, transmission is against the wall in the corner. Maintenance people are not to happy seeing their resident bring a transmission to the complex.. oh well I told them it will dissapear in two weeks.

    [​IMG]

    Top view of cover
    [​IMG]
    [​IMG]

    it has three shift rails so I assume that means three shift forks? I want to pull the top off but with maintenance people kinda being iffy right now I don't want to provoke them.

    Regarding the overdrive, that would be nice in future but with 3.73 axle gears I can honestly live without the overdrive. So if I was able to use the 3:15 transfercase gears and not be able to use an overdrive that would be okay with me.

    I didn't find this, one of the members here sent me a pm about the posting on craigslist. :)
    we got a good group of people on here. :)
     
    Last edited: Oct 4, 2013
  10. Oct 4, 2013
    oldtime

    oldtime oldtime

    St. Charles,...
    Joined:
    Aug 14, 2006
    Messages:
    3,466
    Piffey,
    This is obviously not a factory assembly.
    The aluminum transfer case adapter alone is a dead give-away.

    The special OD bowl gear [#911098] is a must if you want O.D. with Terra low 3.15.

    The T18 maindrive stickout is 6-1/2 IF it has a Ford maindrive gear.
    This is a 1979 or later version of the T18. (aluminum shift forks) (reverse is over and back)

    I suggest you sell the D20 with Tera low unless you specifically want a D20.
    That gearset alone cost someone about a grand.
    The T18 with AA adaptetr can probably be used as is unless it does not have a Ford maindrive gear (input).
     
    Last edited: Oct 6, 2013
  11. Oct 4, 2013
    tarry99

    tarry99 Member

    Northern California
    Joined:
    Oct 29, 2012
    Messages:
    3,784
    I thought someone mentioned an adapter from the Tranny to the Bell Housing???? I don't see it........just the one on the transfer case which is normal........and the bosses tell me again that it is a Ford B&W Tranny............There should also be a boss on the other side that is offset from the others........... that tranny will go right up to your stock aluminum Buick Bell housing with a few mods............Good catch!
     
  12. Oct 4, 2013
    piffey263

    piffey263 Active Member

    Medford, OR
    Joined:
    Oct 16, 2008
    Messages:
    1,214
    Tarry: I was the one who mentioned buying an adapter to go in between the bell housing... I thought it was a jeep t-18 not a ford.... so my bad.


    oldtime: okay, the main input shaft was really short but can't find a ruler or tape measure to confirm the 6.5 at the moment.

    I don't necessarily need a dana 20, I just wanted the lower gears out of it. I could use the money for actually completing the swap if I sold it.
     
  13. Oct 4, 2013
    oldtime

    oldtime oldtime

    St. Charles,...
    Joined:
    Aug 14, 2006
    Messages:
    3,466
    You'll want to seperate the D20 from the T18.
    You will not be able to use the T18 mainshaft gear (transmission output)
    D20 will have a 26 tooth @ 6 spline mainshaft gear.
    If you currently have a T14 you mainshaft gear is 29 tooth @ 10 spline.
    You will need to find a common 29 tooth maindrive gear to fit the 6 spline mainshaft of the T18 transmission.
     
  14. Oct 4, 2013
    oldtime

    oldtime oldtime

    St. Charles,...
    Joined:
    Aug 14, 2006
    Messages:
    3,466
    Or forget the mainshaft gear and install a 29 tooth overdrive onto the D18.
     
  15. Oct 4, 2013
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Medford Mass USA
    Joined:
    Aug 10, 2003
    Messages:
    23,596
    Good advice from Ken. Separate them and sell the transfer case. Used should be at least half-new, so price the D20 accordingly.

    I'd go with the Dana 18 and the T-18, and run it. The Dana 18 already has a pretty good reduction ratio, and you'll have that combined with the 6.32:1 1st.
     
  16. Oct 4, 2013
    colojeepguy

    colojeepguy Colorado Springs

    At the foot of...
    Joined:
    Apr 4, 2010
    Messages:
    7,110
    I think if it was mine, I'd use it as-is. Normally, I'm not a fan of the 20 tcase, but with the 3.15 low range gears & the compound low in the T-18, you'll have all the low gearing you'll ever need. Find yourself a centered D44 rear axle with 3.73's and you'll have a nice setup.
     
  17. Oct 5, 2013
    piffey263

    piffey263 Active Member

    Medford, OR
    Joined:
    Oct 16, 2008
    Messages:
    1,214
    funny, I had the nice centered dana 44 and I sold it.

    okay, just wanted to clarify.

    would the bearing collar already be machined down if this was a ford transmission mated to a AMC motor?
    If not I will just get the piece from novak

    I need to use a ford clutch I assume, but can I use the pressure plate I have? I maybe have 200 miles at most on a new clutch, pressure plate, flywheel surfaced.

    I saw partsMike has a 10.5 ford clutch that is why i'm asking. Pilot bushing i'm aware I need a different one
    I read about a few members getting new pressure plate and clutch from a 90's ford from flaps. Just don't know if its possible to use the the buick pressure plate.

    then I just enlarge holes top holes, drill middle holes, weld two on the bell housing bolt hols and tap, obtain the new bull gear "29 tooth 6 spline" then install with the dana 18. Get the rear driveshaft shortened, and get a new front driveshaft.
     
  18. Oct 5, 2013
    tarry99

    tarry99 Member

    Northern California
    Joined:
    Oct 29, 2012
    Messages:
    3,784
    Yep it would be nice to have that centered rear Dana 44 again.............. You'll have to measure the hole in the current Bell Housing and then measure the front collar.......that part can either be turned down or purchased. The Pressure plate should be able to be used again from your old 225 as it is already setup for a Buick Flywheel.........just needs to be the same size disc for the PP.......when you go to buy the disc take your old PP.......also close attention needs to be paid to the throw out bearing length............although what you have is probably the right one although the collar OD may be different than what your currently have..............when you get a chance measure the input shaft stick-out length from the face of the tranny to the pilot tip should be about 6.500" to 6.625" in length..............and yes you will have to get a Ford disc to match the input spline and also the pilot bushing.
    If your not in a hurry look around for another centered flanged D44 rear axle...........it will bolt right in and then you can use the D-20 transfer case with the 3:15 gears if you want!..........
     
  19. Oct 6, 2013
    '74Renegade

    '74Renegade Active Member

    Fair Oaks, CA
    Joined:
    Sep 1, 2005
    Messages:
    1,275
    You want to buy it back? ;)
     
  20. Oct 6, 2013
    nickmil

    nickmil In mothballs.

    Happy Valley, OR
    Joined:
    Sep 23, 2002
    Messages:
    12,529
    Food for thought, you can use the Dana 20 3.15 gears to build an 18 transfer case. You just don't use the rear output slider gear...


    Sent from my iPhone
     
New Posts