TH400 question

mudracer said:

oh, ok, i did a little research, and I must apologize.

the quadratrac was available with a kit to convert it to 2wd with a .16 overdrive.

now the question remains.... why?


oh well.

Click to expand...

I got mine that way. The truck originally belonged to a WA Supreme Court judge and he was probably told it would get better gas mileage (and it does decent with the way I set it up) The OEM 360 4 bbl got @10 mpg on a good day. With the PT/OD kit, it probably got closer to 12-15 which is a 20-50% increase in fuel economy (makes a difference if you run long distances like I do from Seattle to Index or up to Canada several times a week/month hauling cars/parts or building materials)

never mind.

I give up.

JPTHING said:

I just thought it would be better than this tired TF727 which I filled with water during the floods. The crazy part is that I changed the fluid twice, and it drives fine, even after I had driven it 2 days with water in it. The fluid looked like strawberry milk. The main reason I want to change is because I don't want the QT, I think I will maybe go with a NP231 with an SYE. I really want a cast iron, gear driven, fixed yoke T-case.

Click to expand...

A flush is what is really needed to clean it out. Are you sure it's a QT? (NP219 since it's behind a 727. Used factory '80 till early '82) The shifter has high, high lock (aka Edrive on some), neutral and low lock. NP208 (avail option on low buck models '80 to '89 and all std trans FSJs '80 up) has 2hi, 4 hi lock, neutral and 4 low lock. With locking hubs you can also get 2 low with the hubs undone.
If it's Selectrac, and pre '86 then it probably has the stupid vacuum front axle and either NP229 (available '82 to '91 except '86) or NP228 ('86ish) tcase which are the same except the NP229 has a viscous coupler (like a posi front and back in 4 hi) and the NP228 doesn't (it's like an open diff in 4 high) The NP219, 228, 229, 119, 128, 129 are all the same length (latter 3 were used in AMC Eagles with no low range) but the NP208 is shorter on the back (because it's a solid drive unit so the extra space wasn't needed to be wasted)


If you can find a LH drop Dodge NP205 with 23 spline (check the input depth. There is deep and shallow) then you don't need to change the trans but you will have to do some body/floor and driveshaft mods to make it fit. May require gastank mods for clearance too.

Depending on the tcase, a TH400 swap could require gas tank swapping for driveshaft/tcase clearance.
I suggest better trans mount when you work on it (I switched all my mounts to Energy Suspension since they make one for the 6 cyl as well)

I honestly don't think the NP231 (actually, NV231 since it would have to be '91 up for 23 spline unless you find one on a 4 cyl XJ with 3 speed auto) will stand up to the loads an FSJ will put on it. I used to have a link to New Venture's website with all the tcase's strengths and ratings posted (my friend was an engineer on the NV241 4:1 tcase for the Rubicon and he posted those up)

junkyard jim said:

A: I meant that JEEP TH400s and 727s never came with a NP205 (just to clear that up. No misinformation intended)




I'm not telling him what to buy either, just what I have seen works well and is the best bang for the buck since he already has a 727. The way your reply is worded about the TH400 (quote: keep it and shitcan the QT) and QT (plus your lack of knowledge how they work, which makes them voodoo to get rid of in many people's book) lead me to believe you didn't know what you were talking about either. (like those people who still insist Chev or Ford made ALL AMC's motors or that it's a piece of cake to drop a Chev motor in place of an AMC and somehow miraculously get more power from a lower torque small block and somehow increase the value of an FSJ till they try to sell it)

I reread what you wrote about flushing his 727 and it still going strong, but the next reply (aimed at me) could easily confuse him into thinking he should get a TH400. I'm still waiting to see if he has a NP219, NP229, NP228 or something else shoehorned in there (if it doesn't already have a NP208) and wonder why he wants to change it out if it still works.



And for what purpose does he need to run such a heavy tcase? The few people I know that put an NP205 into an FSJ weren't happy with it due to having to chop the floor to clear it or adding 3" body blocks and a custom trans crossbar to keep it up there.


PS: I also wrote for FSJ magazine.

Click to expand...

Ok, heres a question...

why cant you take the parts out of a 727 that was bolted to a NP205 transfer case, you know, the output shaft, the adapter... just those two things, and install them into a 727 behind his engine?

Why cant you put a 2wd output shaft into a jeep th400 and then stab the np205 onto it? Arent these parts also available and offered from a manufacturer?


Please, dont tell me this wont work. I think we both know better.

Sure, its not "BOLT ON". Nothing is. you might have to take it apart to bolt it back together.

As for why he needs it? ask him, he posted it. Just dont tell him you cant get there from here, when you know you can.

As for writing for a magazine, youre bragging?

the next thing youre gonna tell me is that my ford NP205 isnt bolted to my chevy th400... I cant wait for this.

mudracer said:

Ok, heres a question...

why cant you take the parts out of a 727 that was bolted to a NP205 transfer case, you know, the output shaft, the adapter... just those two things, and install them into a 727 behind his engine?

Why cant you put a 2wd output shaft into a jeep th400 and then stab the np205 onto it? Arent these parts also available and offered from a manufacturer?


Please, dont tell me this wont work. I think we both know better.

Sure, its not "BOLT ON". Nothing is. you might have to take it apart to bolt it back together.

As for why he needs it? ask him, he posted it. Just dont tell him you cant get there from here, when you know you can.

As for writing for a magazine, youre bragging?

the next thing youre gonna tell me is that my ford NP205 isnt bolted to my chevy th400... I cant wait for this.

Click to expand...

You obviously seem to think he's mechanically inclined. (which looking at trying to put a light duty 231 into a full sized vehicle is something most people wouldn't do as it's weaker or equal to the other FSJ stock tcases except the NP208J)

It cost$$$$ to buy the parts and insert them into whichever trans he choses to run (and miteaswell rebuild the trans while he's at it). PLUS the NP205 requires body surgery and crossmember manufacturing to install for very little added benefit over a NP208.

He asked specifically IF Jeep ever came with a NP205 tcase (answer is from the factory, no)
The NP208J IS a bolt on swap (except the rear driveshaft), but I agree that strengthwise it isn't as tough as the NP205. It is however stronger than a C/D/F NP203 (according to New Venture) or whatever FSJ tcase he has if it's not a NP208 already.

mudracer said:

why cant you take the parts out of a 727 that was bolted to a NP205 transfer case, you know, the output shaft, the adapter... just those two things, and install them into a 727 behind his engine?

Click to expand...

It requires totally dismantling the trans to install. Not a novice task (get the VHS video on building a Mopar trans before trying)


Show me any inaccuracies in that (I do have proofreaders double check what I write for the mag due to my head injury making it not as easy to get across to some people what I mean.)

oy.



fawk it.

Ok so now to answer the questions. First the reason for the idea of the Np231, is that Rick at Snoho. Trans. suggested it would work, and be a better t-case, than my "selectrac" Np229(not QT, I was wrong. I hate these cheesey names for the garbage that Jeep put in their vehicles). The previous Np228 was so worn out that the chain bound up, and cracked the case. Swapped it for the Np229, cause it was free, and got it going in a couple of hours. I want the Np205, cause it is the strongest t-case made for my applications, with 1.5" gears(bigger than the Atlas). The reason I asked about the Th400, is cause it was the only tranny that came to mind that was used with Jeeps, and GM who put it with the Np205. The other reason I asked if Np205's came in Jeeps, is cause I didn't want to do axle swaps(PITA), and the round Jeep bolt pattern, is the same as Chevy Np205's (PSD), I was thinking that if they were made for Jeeps, I could have avoided having a custom input shaft for the Np205 made to accept the 23 spline output of the tranny. Honestly if my wife didn't like this Waggy being an Auto so much, I would have changed the Auto, and put in a Np435, (same bellhousing to trans bolt pattern as some Jeep manual trannies) with the Np205. Btw I like the tranny I have(whether it be the TF999, or theTF727, I don't know the difference, and I know nothing about them other than they were also used in Chrysler products), I was just thinking that the Th400 might be stronger. Also I had the Np208 in 3 K5's, and I hated every one. Now if there was a 23 spline Np205 made, what it was in, and if it was for a Chevy, can the input shaft be installed into a Ford Np205 t-case? I will make an adapter, to bolt the tranny to the Ford T-case. And as for the cross member, cross members are easy to build. I really appreciate all the info.

JPTHING said:

Ok so now to answer the questions. First the reason for the idea of the Np231, is that Rick at Snoho. Trans. suggested it would work, and be a better t-case, than my "selectrac" Np229(not QT, I was wrong. I hate these cheesey names for the garbage that Jeep put in their vehicles). The previous Np228 was so worn out that the chain bound up, and cracked the case. Swapped it for the Np229, cause it was free, and got it going in a couple of hours. I want the Np205, cause it is the strongest t-case made for my applications, with 1.5" gears(bigger than the Atlas). The reason I asked about the Th400, is cause it was the only tranny that came to mind that was used with Jeeps, and GM who put it with the Np205. The other reason I asked if Np205's came in Jeeps, is cause I didn't want to do axle swaps(PITA), and the round Jeep bolt pattern, is the same as Chevy Np205's (PSD), I was thinking that if they were made for Jeeps, I could have avoided having a custom input shaft for the Np205 made to accept the 23 spline output of the tranny. Honestly if my wife didn't like this Waggy being an Auto so much, I would have changed the Auto, and put in a Np435, (same bellhousing to trans bolt pattern as some Jeep manual trannies) with the Np205. Btw I like the tranny I have(whether it be the TF999, or theTF727, I don't know the difference, and I know nothing about them other than they were also used in Chrysler products), I was just thinking that the Th400 might be stronger. Also I had the Np208 in 3 K5's, and I hated every one. Now if there was a 23 spline Np205 made, what it was in, and if it was for a Chevy, can the input shaft be installed into a Ford Np205 t-case? I will make an adapter, to bolt the tranny to the Ford T-case. And as for the cross member, cross members are easy to build. I really appreciate all the info.

Click to expand...

ok, for the TF727, if thats what you have... you need the trans from a 88-91 Dodge with a cummins...not that they are easy to find, but the nice thing is that someone will buy the case from you. Well, maybe.

Pull the output shaft from this, and install it into your 727. then bolt on the adapter, and bolt on the transfer case.(np205 from the same truck)

Just so you know, these are a 29 spline male input shaft, and are rare as hens teeth.

If you have the "other trans" the TF518/904 kinda version... get the np208 and be done with it.

If you want a th400, get a jeep th400, and install the tailshaft for a GM car/truck from a trans that has the short tailhousing. the TH400 will bolt to the CHEVY NP205 using the factory adapter. You do have to have an NP205 that was set up for the th400, as the inputs are different between each trans in the GM family. 10 spline male-sm465, 27 spline male-th350, 32 spline female short-th400 32 spline long-late model sm465.

there are a HUGE amount of variations in applications for this transfer case. you cant put a 23 spline input from a dodge into a ford np205 due to the bearing size on the input shaft. If, however, you could find a bearing that was the corresponding size, you probably could. What you will end up asking yourself is this:

Was it worth all the hassle to do?

Only you can answer that question.

and remember, the only limit is the limit you place upon yourself. Dont let someone say that it CANNOT be done. You can do anything you put your mind to. Some things take longer, and cost more.

Maybe I will just have a custom hardened cross shaft made, and bolt a Ford Np205 to a custom adapter.

JPTHING said:

Maybe I will just have a custom hardened cross shaft made, and bolt a Ford Np205 to a custom adapter.

Click to expand...

If you go to a place that sells bearings as a wholesaler with the dimensions that you need, you will probably be able to find a bearing.
you will need to get the following together:

Bearing ID (or the original 23 spline 205 input shaft and bearing so you can measure it)
Bearing OD (for the Ford NP205 input bearing)
Bearing thickness (which if you have both bearings, you can figure out rather easily.

find a bearing that will install in the case, on the input, and youre done.. with the bearing. then you will have to clock the case to fit your adapter, drill and tap some holes, and bolt it up.

thats all there is to it.

well, at least it sounds easy.

the custom shaft is rather spendy.

Edit: theres a place here that sells bearings exclusively. They are called Applied Industrial Technologies 541 672 6950
They do great work with thier customers.

89 MJ 350 np435 np203/205 Hybrid 14 bolt front 14 bolt rear. 39.5" Boggers custom 12" lift
91 YJ 2.5L D60 rear HP D44 Frt. 38.5" Boggers SOA
88 XJ 2dr 4.0 Np435 Np205 8" lift & cut to fit 36" Irok's
88 XJ 4dr 4.0 w/ax-15 4.5" lift 34" LTB's
91 XJ 2dr 4.0 Ax-15 5" lift 33" Boggers
93 ZJ 5.2L 31" Firestones
85 SJ Waggy Grocery Getter

Lemme get this straight. This is your Waggy Grocery Getter we're talking about, right? WTF does a grocery getter need with massive geartrain swapping? Why put a massive, heavy, super-strong t-case in a milk and pototoes rig? I'm confused. You post up a fleet of off-road, super built rigs, spend your time and money on them. Just change the fluid and drive this turd till it dies. If you want economy, buy a honda. You have 6 other off road rigs to drive.

JPTHING said:

Ok so now to answer the questions. First the reason for the idea of the Np231, is that Rick at Snoho. Trans. suggested it would work, and be a better t-case, than my "selectrac" Np229(not QT, I was wrong. I hate these cheesey names for the garbage that Jeep put in their vehicles). The previous Np228 was so worn out that the chain bound up, and cracked the case. Swapped it for the Np229, cause it was free, and got it going in a couple of hours. I want the Np205, cause it is the strongest t-case made for my applications, with 1.5" gears(bigger than the Atlas). The reason I asked about the Th400, is cause it was the only tranny that came to mind that was used with Jeeps, and GM who put it with the Np205. The other reason I asked if Np205's came in Jeeps, is cause I didn't want to do axle swaps(PITA), and the round Jeep bolt pattern, is the same as Chevy Np205's (PSD), I was thinking that if they were made for Jeeps, I could have avoided having a custom input shaft for the Np205 made to accept the 23 spline output of the tranny. Honestly if my wife didn't like this Waggy being an Auto so much, I would have changed the Auto, and put in a Np435, (same bellhousing to trans bolt pattern as some Jeep manual trannies) with the Np205. Btw I like the tranny I have(whether it be the TF999, or theTF727, I don't know the difference, and I know nothing about them other than they were also used in Chrysler products), I was just thinking that the Th400 might be stronger. Also I had the Np208 in 3 K5's, and I hated every one. Now if there was a 23 spline Np205 made, what it was in, and if it was for a Chevy, can the input shaft be installed into a Ford Np205 t-case? I will make an adapter, to bolt the tranny to the Ford T-case. And as for the cross member, cross members are easy to build. I really appreciate all the info.

Click to expand...

I agree on the lameness of the Selectrac. (if the rig is V8, then it's 727. Only the 6 cyls came with 999 stock) Since you originally had a NP228, then your rig is an '86 w/o the vacuum front axle? (that's a good thing!) The Chev NP208 (it has a narrower chain and the slipyoke bites plus who in their right mind uses plastic shift forks!) isn't as good as the Jeep, Dodge or Ford fixed yoke versions.
If you go to an AMC TH400 (Chev is NOT the same case as the Jeep one. The internals are swappable) and input a Chev output shaft that matchs the LH drop NP205 you are going to run.
If you keep the 727, and find a V10 rig 3 speed auto with NP205, then it should bolt right up to your current 727 UNLESS the V10 trans has the output shaft with the pilot shaft. In that case, you need the output shaft as well (The trans was also used rarely behind some early diesels)
I've been kicking myself because everyone told me the V10 and diesel ONLY ran 29 spline so I sold the NV241 DHD I had on EBay without checking. Turned out it had 23 splines (found this out when the guy I sold it to said he was going to swap it to 23 spline, but didn't need to because it already was. I thought he was BS'ing me till I counted the teeth in the pic I took before shipping it!) and I could have used that with my 727 in my '73 J4000. AAAAARRRRGH!
You need the matching TH400 flexplate for your motor (each AMC V8 has a different external balance. AMC 6 cyls are all zero balanced) and the thin sleeve that goes into the crank pilot hole to align the torque converter. (you can get minor vibes without it. What's worse is when people go TH400 to 727 w/o removing that sleeve and end up with a dead trans! The converter gets pushed back through the front pump.)
You need '73 to '79 FSJ TH400 shift linkage. (I can't recall if the steering column is different placement for the arm or not? That may be the deal breaker unless you go floor shift or find a Lokar kit) Since I'm going the other way, we can swap linkages but mine in non-tilt old school column. You'll also need the gas pedal from a TH400 rig for the kickdown switch (again, we can swap) and run a wire to it and from there to the trans.
Gotta go to work for a bit (been home so far today with the worst stomach flu EVER since yesterday so my postings may not have been completely sensical) If I think of more, I'll post up later (cuz I got no life, I'm home for New Year's Eve. I would wish this bug on NO-ONE! Not even Kelly!)


Oh yeah, some later Dodge trucks came with 727 and LH drop NP205. Don't remember when the chanegover was? '83?

TreeClimber said:

89 MJ 350 np435 np203/205 Hybrid 14 bolt front 14 bolt rear. 39.5" Boggers custom 12" lift
91 YJ 2.5L D60 rear HP D44 Frt. 38.5" Boggers SOA
88 XJ 2dr 4.0 Np435 Np205 8" lift & cut to fit 36" Irok's
88 XJ 4dr 4.0 w/ax-15 4.5" lift 34" LTB's
91 XJ 2dr 4.0 Ax-15 5" lift 33" Boggers
93 ZJ 5.2L 31" Firestones
85 SJ Waggy Grocery Getter

Lemme get this straight. This is your Waggy Grocery Getter we're talking about, right? WTF does a grocery getter need with massive geartrain swapping? Why put a massive, heavy, super-strong t-case in a milk and pototoes rig? I'm confused. You post up a fleet of off-road, super built rigs, spend your time and money on them. Just change the fluid and drive this turd till it dies. If you want economy, buy a honda. You have 6 other off road rigs to drive.

Click to expand...

:haha: :haha: :haha: :haha: oh, damn.... signature lines kill me sometimes...i gotta start paying more attention.

Hey Junkyard Jim

I think you are wrong on a technicality. I believe AMC 304 and 360s are internally ballanced, and only the AMC 401 with the forged crank is externally ballanced and it's ballanced via the harmonic ballancer. If I'm correct, the flywheels and flexplates are just ballanced to keep that individual component from upsetting the whole.

mudracer said:

If you go to a place that sells bearings as a wholesaler with the dimensions that you need, you will probably be able to find a bearing.
you will need to get the following together:

Bearing ID (or the original 23 spline 205 input shaft and bearing so you can measure it)
Bearing OD (for the Ford NP205 input bearing)
Bearing thickness (which if you have both bearings, you can figure out rather easily.

find a bearing that will install in the case, on the input, and youre done.. with the bearing. then you will have to clock the case to fit your adapter, drill and tap some holes, and bolt it up.

thats all there is to it.

well, at least it sounds easy.

the custom shaft is rather spendy.

Edit: theres a place here that sells bearings exclusively. They are called Applied Industrial Technologies 541 672 6950
They do great work with thier customers.

Click to expand...

Here's what I found
http://www.high-impact.net/transmission_and_gear/Tcase_NP205.htm

Swapping input gears in NP205s

Dodge, Ford and GM input gears are all internally interchangeable in all NP205s with one MAJOR detail:



GM 27 and 10sp, and Dodge 23 spl all used a SMALL dia input bearing and seal. These shafts can be swapped directly among themselves.



GM32, Ford 31 and Dodge 29 spl used a LARGER dia bearing. These shafts can be swapped among them selves directly



If you want to upgrade an NP205 with a 10,27 or 23 spl input to a 29, 31 or 32 spl input: The case must be fully disassembled and the opening where the input bearing sits must be machined out to accept the larger dia bearing. A larger seal is also used. The adapter or bearing retainer must fit the Larger dia bearing.

I have the 10 spline Np205, So I would think the input shaft would go right in.

TreeClimber said:

I think you are wrong on a technicality. I believe AMC 304 and 360s are internally ballanced, and only the AMC 401 with the forged crank is externally ballanced and it's ballanced via the harmonic ballancer. If I'm correct, the flywheels and flexplates are just ballanced to keep that individual component from upsetting the whole.

Click to expand...

I can show you the balance weighted flexplates/flywheels and harmonic balancers. When AMC raised their V8 block height (made the 290 into 304, 343 into 360 and made a 390/401 casting which looks the same as the others but is internally different) they changed the offsets of the spinning weight of the engine. They just went to an external balance rather than re-balance the whole line (made sense at the time)
You can rebuild any of the AMC motors and have them internally balanced for @$350 extra per motor.

Went to Rockauto for part #s.
'72 304 with 727 or 999 auto: DORMAN Part # 04302 {Gear-Up! OE# 3232140, 3232139 Hollander # 409-503 Teeth 164 Pitch 12-14 O.D. 13.83" With Weight #3232140}

'72 360 with TH400: DORMAN Part # 04303 {Gear-Up! OE# 5351821 Hollander # 409-553 Teeth 164 Pitch 12-14 O.D. 13.83" Without Weight #5351821}

'72 401 with 727: DORMAN Part # 04036 {Gear-Up! OE# 3214090, 3232141 Teeth 164 Pitch 12-14 O.D. 13.83" With Weight #3214090}

'72 401 with 401: DORMAN Part # 04369 {Gear-Up! OE# 5351822 Hollander # 409-554 Teeth 164 Pitch 12-14 O.D. 13.83" With Weight #5351822}


The pic shows a TH400 flexplate for 360 (note the cutout in the bottom of the pic is nearly full. The 401 version is almost solid and 304 version has more cut away. 6 cyl is fully open) I found this out when I converted the 304 in my '73 J4000 from 727 to TH400 and I had a bad vibe when I revved the motor till I swapped it out (I tried using the 360 one because everyone said it was the same)

JPTHING said:

Here's what I found
http://www.high-impact.net/transmission_and_gear/Tcase_NP205.htm

Swapping input gears in NP205s

Dodge, Ford and GM input gears are all internally interchangeable in all NP205s with one MAJOR detail:



GM 27 and 10sp, and Dodge 23 spl all used a SMALL dia input bearing and seal. These shafts can be swapped directly among themselves.



GM32, Ford 31 and Dodge 29 spl used a LARGER dia bearing. These shafts can be swapped among them selves directly



If you want to upgrade an NP205 with a 10,27 or 23 spl input to a 29, 31 or 32 spl input: The case must be fully disassembled and the opening where the input bearing sits must be machined out to accept the larger dia bearing. A larger seal is also used. The adapter or bearing retainer must fit the Larger dia bearing.

I have the 10 spline Np205, So I would think the input shaft would go right in.

Click to expand...

if you want to put the 23 spline input into a ford NP205 , you will have to get a bearing. the 23 spline input shaft is smaller than the ford 31 spline input shaft. this is what you had first mentioned.

If you are installing it into a chevy 4speed 10 spline np205, itll go right in like gangbusters. all thats left is to get the bolt pattern on the case.

post pics, show us how youre doing with it. I think this kind of thing would be great for everyone to see.