208or d20.........

[Simple Kind of Man]

Pros and cons. will either work on a 727 or th400. Is one that much stronger than the other?

[Heimeken]

Not sure if one is stronger than the other, but I have heard better things of the 208. The 208 only bolts to the 727. AFAIK the D20 came behind manual trannies, not sure if it came behind the TH400, but the Quadratrac did and it's a good case.

[jode]

Originally posted by Heimeken:
AFAIK the D20 came behind manual trannies, not sure if it came behind the TH400Yeah it did. But the TH400 output shaft for QT and for D20 is not the same. And IIRC, an adaptor is required.

[Knucklehead]

208 has a 2.61:1 low range.
D-20 has a 2.0:1 low range.

I think that the 208 is at least as strong as a D-20. I have heard the 208 is even stronger.

[Tad]

I am not real sure what is stronger.
I am real sure I am tired of finding TH400-Dana20 adapters.
Those chevy desert racer guys ran the 208 behind those high horsepowered big tired rigs for quite some time.

[River Beast]

the GM208 that was mated to the TH400 can be used on the AMC TH400 with the GM TH400 tailshaft and adapter from the GM TH400

the 208 was used behind the 6.2L diesel CUCV ( K30 1 ton 4x4) with 4.56's and a detroit in the rear... I'ld say it can take a good beating and survive no problems....

you can mount the Jeep NP208 to the TH400 as well... you just need the TH400 adapter, input gear for the GM208 and the tailshaft for the tranny to have a driver drop, fixed yoke 208 behind the TH400 if you wanted to...

adapters, tailshafts and inputs are all that is needed to swap in any of the 208's out there... they are all round pattern... Ford, Dodge Jeep and GM.. just mix and match what you need to work...

[Crazy_Jeepman]

Originally posted by River Beast:
you can mount the Jeep NP208 to the TH400 as well... you just need the TH400 adapter, input gear for the GM208 and the tailshaft for the tranny to have a driver drop, fixed yoke 208 behind the TH400 if you wanted to...

adapters, tailshafts and inputs are all that is needed to swap in any of the 208's out there... they are all round pattern... Ford, Dodge Jeep and GM.. just mix and match what you need to work...I found a Clocking Issue with the Jeep NP208 and the Chevy TH400 to NP208 adaptor. :eek: May and am sure will apply to other swaps. I am in the middle of resolving it now. :rolleyes:

[Cecil14]

Could you redrill the adapter to "rectify" the issue? I know sometimes there's enough metal to move the holes over an inch or so to get the case where it will work.

Anthony

[Crazy_Jeepman]

At this point I am sure it can be done. I had bolted the TH400 and the Jeep NP208 bolted together with a few bolts. I went to put the rest of the bolts in and discovered they are not uniform patern, but are of an indexed patern. It does look like I can leave one bolt out and the T-case will clock back to where it should be. I will be looking into this in the next day or so.

[River Beast]

thanks for the clarification Pete.... I was SURE you would chime in... ;) I couldnt remember the particulars we discussed

[Tad]

Originally posted by Crazy_Jeepman:
I found a Clocking Issue with the Jeep NP208 and the Chevy TH400 to NP208 adaptor. :eek: May and am sure will apply to other swaps. I am in the middle of resolving it now. :rolleyes: Hmm, better open up that Dodge 208 that came today.

EDIT: Ok just checked, the Dodge 208 is clocked about 30 degrees off from the chevy 208 it looks like. Not sure what to do here, maybe use the front half of a chevy case?

It does match the adapter on the 727 perfectly, but that will not help me at all.

Any news here folks?
I'm begining to wonder if it is even possible to get this Dodge 208 onto the back of a TH400 with the different spline counts and the clocking issue.
:(

[Crazy_Jeepman]

I am confident I have the Jeep 208 clocked to where it will work. I did leave one bolt out. It is off by about 1/8" so I could oblong that hole to get a bolt in it. If you want I can send you the TH400 to NP208 adaptor and you can see what you need to do to get it to work, I am a couple months from needing it anyhow.

[Simple Kind of Man]

Ok I will try to clarify my post. I am getting a '77jeep that has a th400 & q-trac also getting a th400 with the d20. I am not sure that the d20 was mated to the th400 or not, how can I tell? I am somewhat green where drive lines are concerned. Where there any jeeps that had th400-d20 combo? Can I mate the d20 to a 727 without adapters? If I go the 727-208 will they bolt up as long as the 208 is from a jeep? I'm sorry for so many questions but I'm just not a fan of "full time 4wd"

Thanks for all info
Tim

[full_hydro]

Yes, my '72 wagoneer came with a th400/dana20. there is an aluminum factory adapter that mates the two together. the adapter is prone to failure.

i haven't had issues with my dana 20.. yet. the two weak points on it seem to be the adapter and rear output. Earlier versions of the dana 20 had a 10 spline rear output, and later versions had a stronger, 26 spline rear output.

[mountainlander]

Stab in the dark here, by noob....

Hmm, I know with the NP231 there were different sizes of chains in different applications. Is this the case with the 208 as well?

For example a np231 out of a chevy s10 has a 0.5 inch wider chain that can be swapped directly into the jeep case....

Maybe one ton 208s have different chains?

[River Beast]

If the TH400 was from a QT FSJ... the tailshaft will be 10 spline... unique to the QT... it will have to be swapped with a chebby tailshaft...

now.. if the D20 is from an auto.. you are in business... if not... the input gear of the D20 will have to be swapped to accept the 32 spline shaft needed from the TH400...

the QT adapter will not work with the D20.. you need a D20 adapter for the TH400/D20 combo

[Tad]

Tim,
I caught your post/message in Gen Disc. I'm not a tcase guru, I'm probably more close to your position trying to figure this whole situation out.

I'm swithing over to a 208 from a Dana20 for the lower gearing. The Dana20 is a good case but I don't think it will work real well for me with the SOA and the 14Bolt rear. I'm also a bit bored with trying to find reasonably priced adapters.

Pete, thanks for the call last night, was sleeping like a baby, sorry, it's been two long 16 hour days in a row for me.

Here is where I am at with this.
I'm accumulating parts for the summer, I want to do this all at once to avoid dupicating driveshaft work and whatnot.

I have the TH400, 32 spline output.
I have the Dodge 208, 23 spline input.
I know I need the 400-208 adapter.
I know the Dodge 208 is clocked differently, probably like the Jeep 208.

I trust Pete fully in that we can clock the adapter (no need to send it, I'll find one) and make this line up. I'll play more with the 727 one today and see what can move where hole wise.

What I think I need to know here is:

Am I changing the TH400 output shaft?
(it looks too long, 32 spline from Dana20)

Am I changing the 208 input gear?
(23 spline)

Does the TH400-208 adapter use a bearing like the Dana20?
(I never see a bearing in the ones for sale)

I keep seeing this adapter offered up as a TH400-NP part...
http://i5.ebayimg.com/03/i/01/5c/a8/ed_1_b.JPG

...will it work?
(I thought I read someplace that although it bolts up it has different dimensions or something, it also does not look to have much room to play with elongating any holes)

or...
Is this the only style I should be searching for?
http://i9.ebayimg.com/02/i/01/7a/9e/7a_1_b.JPG

Got lots of time to figure this out, just only want to do it once.
TIA folks.
smile.gif

[Crazy_Jeepman]

Am I changing the TH400 output shaft? Yes

32 spline from Dana20? Wrong one

Am I changing the 208 input gear? Yes

Does the TH400-208 adapter use a bearing like the Dana20? No, its wide open. Not even a seal.

The Adaptor you show at the Top is a TH400 to NP T-Case. If it has 6 holes Trans side and 6 round patern T-Case side thats the one. You need a matching tailshaft for the TH400 as well.
I think only one bolt needs to be left out, and that will allow you to clock it to where you need it to be. I think only one bolt hole is drilled out of patern on the T-Case and it is not by much. Looking at the 2nd Pic you posted the patern looks very uniform, though the two bolt holes at the very bottom do apear to be closer together, and that would be the side I left one out. Since your Dodge case matches the Jeep TF727 perfectly then I will assume that it will work as mine has. I left out one bolt and it has clocked to where I think it should be. Though it is hard to tell laying on the floor and nothing to get an idea where it should actually be. I will put the Jeep adaptor back on and mark the mount so I can refferance to the Chevy adaptor. I will get some detailed Pics of what I do to make it go together.

[ March 18, 2004, 04:49 AM: Message edited by: Crazy_Jeepman ]

[Rande]

International used the Dana20 passgenger side drop behind the Chrysler 727 tranny.

There's another possibility for our Jeeps. I am going to find one for myself and then get a look at what needs to done. I don't know what the spline counts are, don't know what the adapters look like yet.

I have a 1980 727/NP219 set-up that I need to change to passenger side drop.

[Tad]

OK, played with the clocking and the NP adapter on the Dodge case, it looks doable, might be a hair more than 1/8" off on that one bolt hole and it will clock either way.
I was having some trouble vizualizing it since the 727NP adapter when clocked goes a full 30 degrees either way and doesn't look right. Seems like the TH400 NP adapter will only clock it 15 degrees which may be just about right.

[gsmikie]

ok check this out you can run a 208 on a 350 or th400 all you have to do is change the input gear in the t-case as for the adapter the last one i bought at the dealer was $80.00 but now comes the trick part you can run a 241 transfer from a late chev-dodge-ford with the adapter from a late 480LE and they can be had on e-bay for 15.00 up chev ran a 208 in all of their diesel trucks 1980-1985 and blazer but they used a th375 output shaft in the th400 this shaft has th350 spline count and dia and if you use a adapter from a 480LE ie is clocked right and all the late t-cases 241 have 32 spline count and they come man or elec shift and are part time cases and they can be had cheaper than 208's i have one with over 200,000 miles on it and have no problems and i use it at least twice a week as for the dana /spicer 20 they came behind th400/3 and 4 speed man and behind the 727 in scouts and you can use the adapter from a scout in the jeep 727 the 208 is good i think the 241 is better and both drop on both sides

[gsmikie]

i forgot to say that with the 241 adapter you can run the 2 wheel drive short th400 output shaft and dont for ed moser .com will turn and respline your shaft's trans/axel/to any spline and lengeth you want last time i had him do axels it ran $55.00 per axel with a 72 hour turn around

[Tad]

Gee wiz Mikie, gonna take me an hour to sort thru that info (I ain't that smart), I best go make some coffee.