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

dana 18 low gear kit

Discussion in 'Early CJ5 and CJ6 Tech' started by evanjm, Apr 21, 2008.

  1. evanjm

    evanjm Yeah, it's got an F-head.

    i know there's a 3.15:1 kit for the d18, but i remember reading somewhere that someone had produced a kit that reduces the gearing even lower. has anyone heard anything about this?

    thanks,
    evan
     
    evanjm, Apr 21, 2008
    #1
  2. Mcruff

    Mcruff Earlycj5 Machinist

    Jack O'Brian kits are 4.0:1 if I remember right.
     
    Mcruff, Apr 21, 2008
    #2
  3. Brian P

    Brian P Member

    Its a shame that there does not seem to be any low gear kits for the older Spicer 18.
     
    Brian P, Apr 22, 2008
    #3
  4. tallyjeeper

    tallyjeeper Member

    So, the Jack O'Brian kit is also for the single stick D18? Can the "newer" D18 be converted over to a twin stick set-up?
     
    tallyjeeper, Apr 22, 2008
    #4
  5. 66cj5

    66cj5 Jeep with no name

    yes. matter of switching the shift rods and front cover.
     
    66cj5, Apr 22, 2008
    #5
  6. Mcruff

    Mcruff Earlycj5 Machinist

    My 71 single stick was converted to twin stick almost 3 years ago.
     
    Mcruff, Apr 22, 2008
    #6
  7. nickmil

    nickmil In mothballs.

    My goodness, has it been that long?:shock:

    Here's the last contact info I have for Jack O'brien:

    O'Brien's 4 Wheel West
    1302 Hidden Court
    Roseville, CA 95661
    (916)773-3278
     
    nickmil, Apr 22, 2008
    #7
  8. DanStew

    DanStew Preowned Merkin salesman Staff Member

    Oh and prepare for $$ shock. Last i saw the price it was pretty steep. Good gears and worth it, but just a little more since it isnt a common product.
     
    DanStew, Apr 22, 2008
    #8
  9. 1969_CJ5

    1969_CJ5 Sponsor

    1969_CJ5, Apr 22, 2008
    #9
  10. Warloch

    Warloch Did you say Flattie??? Staff Member

    Some food for thought (as I looked into it as well)
    T90 5.38axle 2.46tcase = 37 Crawl
    T90 5.38axle 3.15tcase = 47 Crawl

    SM465 4.88axle 2.46tcase = 79 Crawl
    SM465 5.38axle 2.46tcase = 87 Crawl

    I believe the biggest bang for the buck is the 4 speed and OD.

    YMMV...
     
    Warloch, Apr 22, 2008
    #10
  11. jasonjeep

    jasonjeep New Member

    if u are going with the advanced adapters kit ,.its the terralow kit built by teraflex. and they charge about 100.00 more than 4wheel parts for the exact same thng i juast finished this same project and i did alot of research before i started now its in im running it behind an sm420 with 373 gears and 35 in tires and beleive me im impressed with the crawl ratio somewhere around 90 to1 so iwould seriously thnnk about this rout for a d18 large hole .oh by the way ,when did they build a single stick d18?,
     
    jasonjeep, Apr 23, 2008
    #11
  12. Mcruff

    Mcruff Earlycj5 Machinist

    All the v6 model cj's came factory with a single stick dana 18.
     
    Mcruff, Apr 23, 2008
    #12
  13. warrpath4x4

    warrpath4x4 Member

    my 65 cj6 has the 4cyl and a single stick D18
     
    warrpath4x4, Apr 23, 2008
    #13
  14. Brian P

    Brian P Member

    I am leaning that direction. Looking into a T98 from Herm.
     
    Brian P, Apr 23, 2008
    #14
  15. windyhill

    windyhill Sponsor

    Another thing to check on is weather you can run an overdrive with the lower 18 gears. I think O'Brien's kit doesn't work with overdrive? Ask green71, He ran into this problem.
     
    windyhill, Apr 23, 2008
    #15
  16. Warloch

    Warloch Did you say Flattie??? Staff Member

    Herm offers a bowel gear that work for the terra low - add about another $700 to the option.
     
    Warloch, Apr 23, 2008
    #16