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automatic transmission swap cj2a questions

Discussion in 'Flat Fender Tech' started by canuck2a, Apr 21, 2009.

  1. Apr 21, 2009
    canuck2a

    canuck2a New Member

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    Mar 9, 2009
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    Have a couple of questions about possibly putting a automatic tranny into cj2a.
    I have been researching and have read that a th350 trans will fit into a cj2a behind a gmv6 with some modification. But driveshaft length has to be monitered carefully. But I have been reading and thought that a TF999 or Tf904 might be a good swap as well. Du to the fact that they (if i read correctly) are shorter in length than the th350. And seem to be pretty beefy. Is this a viable option???? what are the downsides to the TF tranny??? I know Advance Adapters makes an adaptger to fit this tranny to a gm engine. But will a d18 bolt up to this tranny or does anyone make an adapter??????
     
  2. Apr 21, 2009
    Kman

    Kman Member

    Middletown...
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    Feb 27, 2005
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    I'm not to impressed with the TF999 thats in our '89 Lerado but then again I'm not a fan of auto trannies. I also have one of these in an '84 Lerado parts Jeep so you can get them that will bolt to a Dana 300. I'm not sure if there are shift kits available for them or not. I did find a write up on relocating the breather vent for water crossings.
     
  3. Apr 21, 2009
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Medford Mass USA
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    Why do you think the TF999 with adapter is shorter than the adapted TH350? I would be surprised if it is. The 904 and 999 came in CJ-7s from 1980 on with the D300, and it's not a popular swap for the CJ-5. I would have expected it to be more popular if it were a good junkyard swap.

    Supposedly the TF999 can be built for big power, and works well with passenger side drop. It's a NP pattern, so you'd need to use the D300 and a centered rear axle. There isn't anything I know of to prevent using it other than excess length. Sorry, I don't know much more about it.

    There's also the Powerglide and the Ford C4 that are possible. I think the C4 is fairly short, but the TH350 ratios are superior.

    Novak sells the TH350 adapter - you could call them and ask them why you should use their adapter rather than the junkyard TF999, or the C4 (adapter available from Advanced, I think).
     
  4. Apr 21, 2009
    Warloch

    Warloch Did you say Flattie??? Staff Member

    Falcon, CO
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    The reason your not getting alot of info about an auto in a flattie is that it just does not work well. It does not mean it's not possible - just not practical for most folks. The few (let me emphasise FEW) auto swaps I have seen have been very difficult, HIGHLY custom (as in most had thier own machine shop to make adaptors) in order to get them to work 'right'.

    The long drive train causes ripple effects in problems from position to drive shaft length, pinion angle, lift problems and cooling issues.
     
  5. Apr 21, 2009
    canuck2a

    canuck2a New Member

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    can you install a d18 on the tf999/904 . The only reason i think it is shorter than the th350 is that i read the specs on both and i beleive i read that the 904 is 16" and the th350 is 20 or 21" But please correct me if i am wrong. But the main thing would be that i would like to use the d18 for passenger drop. (I woiuld like the jeep to appear somewhat stock at first glance, until the hood is popped and closer inspection but want it a little more reliable and user friendly.)
     
  6. Apr 21, 2009
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Medford Mass USA
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    No. The pattern and the splines on the Jeep TF9xx are way different from the Dana 18 pattern. NP (New Process) pattern with 20-odd splines, as I wrote above. The Dana 18 has the texas pattern and has 6 splines.
     
  7. Apr 22, 2009
    canuck2a

    canuck2a New Member

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    SO if a person were to go with an auto it would probably be wise to go with a th350 as it is more economical, dont need a adapter to mount to the engine, and they are pretty cheap to find, you only have to buy an adapter for a tcase. What all would a guy need for an auto tranny. for this conversion other than tranny, adqpter, mount,
     
  8. Apr 22, 2009
    Daryl

    Daryl Sponsor

    Bonney Lake, WA
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    I have been running turbo 400s in flatties for over 20 years now. They bolt up to buick v6s as they bolted to 350s stock. These trannies are still very easy to come by. With a centered 44 rear out of a DJ you can still have a 14-15" rear driveshaft. All the parts necessary are stock Jeep parts and are still cheap. No need to spend 500 on an adapter when you can still find motor, trans, and tc for less then that. The avatar pictured is a 231/400/20. I have put over 20,000 miles on it.
     
    Last edited: Apr 22, 2009
  9. Apr 24, 2009
    farm1810

    farm1810 Member

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    I'm curious. To the fellow who has put a 400 turbo in his CJ2A; did you need to use a 2 piece from driveshaft with carrier bearing over on the frame like a Commando in order to clear the case / oil pan on the transmission? I put a 289 Ford and C4 in my CJ2A. The rear driveshaft was a little short, and of course had to lengthen the front. I did put beveled shims between the rear springs and the rear differential to reduce pinon angle. I had 2" lift springs on it also. The other thing was / is that I was using the Warn Overdrive and would need to push the C4 into neutral to shift into / out of OD on the fly. Generally I just shifted into / out of OD at a stop, put into park, shifted, then went on. I did add an addtional, bolt in cross member toward the front of the engine just because the distance from the cross member by the radiator (which I moved forward, cross member and radiator) to the transmission / transfer cross member becomes a pretty long span. So I added one by the engine mounts that I formed to be pretty close to the engine oil pan so it didn't hang down too far to hit obstacles. I also had to find an early Bronco oil pan and oil pump pick up tube, as the car pans had a front sump and hit the Jeep front differential. It was a lot of work, but very reliable once completed. Used the Advance Adapters kit which was the C4 to D20 adapter and output shaft for the C4, bearing, seal, etc. Kit worked great. You must have the additional seal between the transmission and transfer case to keep ATF out of the transfer case.
     
  10. Apr 24, 2009
    Daryl

    Daryl Sponsor

    Bonney Lake, WA
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    The 400 has more room then most 350s for the front driveline. The pan doesnt stick over quite as far. It helps to use 2" lift springs to give a little more clearance. It is one big jigsaw puzzle, but that is what makes it a challenge.
     
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