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Discussion Starter #1 (Edited)
I have a stock 313K farm/trailer haulin truck/flatbed 1990 Dodge 350 4x4 that I broke the 727 trans case, not long ago.

I have found that case part to be stupidly hard and costly to come up with.
So I have been exploring options, bringing me to this site.

I have a Chevy THM400 ready to go I even put around 50 miles on the rebuild (test drive) before the rest of the truck got scraped.

I have explored the 4BT to Chevy Automatic Auto, trans adaptation and find 2 methods are available.

#1 spend over $1400 on this


#2 Find a P30 bread van that has had a Cummins put into it after it was sold. The cost is appealing but with the multiple parts I have seen pictures of that it takes for that to happen, I find no one seems to talk much more then about this combination other then some 10* motor slant. I would either have to change that motor mount (maybe exhaust ++?)

V/s the

"tilt the trany 10*",

has any one tried a set up like the last 2 mentioned or seen the last (trans tilted) working ok?

Are there any other options I have missed?


wazz :beer:
 

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Discussion Starter #2 (Edited)
oops I forgot to check the subscribe button :dustin:

BTW this site has a great search function!

key words for the search
6BT 4BT Cummins 3.9 3.9L 5.9 5.9L to TH400 TH 400 THM400 THM400 to 1989 1990 Dodge 205 23 spline Transfer Case
 

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Are there any other options I have missed?wazz beer:
Hi, if you are set on using the TH400 then I think thats about it. You say you drove the TH400 for 50 miles before it was scrapped was it a diesel? Have you tried getting a replacement 727 rather than just the case as that would probably be your easiest option IMO especially if you were happy with it before. How about a 2nd gen engine adapter and a 47rh then you gain O/D.

Gaza
 

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I have done this. You will need a cable modulator to make this work right. I am using the bread van modulator and it is not real great; 2-3 shift is early and soft. The TH400 also requires a kickdown, but you could probably delete since the 6B will not usually need it. Pulling a load you could manual shift it.

I have to say that I would suggest finding a direct replacement. You might save a few dallars, but the time for the coversion and the little stuff that will add up is hardly worth it. I used the chevy because it was in a early chevy 4x4 truck, and staying chevy made the conversion easier and cheaper.
 

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Discussion Starter #5 (Edited)
Thank you for the replys and information!

Hi, if you are set on using the TH400 then I think thats about it. You say you drove the TH400 for 50 miles before it was scrapped was it a diesel? Have you tried getting a replacement 727 rather than just the case as that would probably be your easiest option IMO especially if you were happy with it before. How about a 2nd gen engine adapter and a 47rh then you gain O/D.

Gaza

Nope I am open for most any option, the THM400 was from a Small Block, but yeah both of your replys made me start thinking about the shifting points of gas v/s diesel, even though they are tuneable under the vaccume hose on the modulator for cars, the diesel one is most likely not adjustable. humm.

I did check into a 727 bought out right as a complete unit and I just have a hard time swallowing $1500 for a 3spd Auto, especialy after destroying this one in less than 120 miles on its trip of me owning the truck, (this 727 was also rebuilt less than 10K miles ago).

I have bought 3 dodge rigs in the last 2 years and all 3 have poped transmissions (2004.5 Cummins is on its 4th transmission in 60500 miles, 79 440 Motorhome 727, and now this 1990 CTD 727), my luck with Dodge transmissions is not been a good experiance so far.








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turbos10

I have done this. You will need a cable modulator to make this work right. I am using the bread van modulator and it is not real great; 2-3 shift is early and soft. The TH400 also requires a kickdown, but you could probably delete since the 6B will not usually need it. Pulling a load you could manual shift it.

I have to say that I would suggest finding a direct replacement. You might save a few dallars, but the time for the coversion and the little stuff that will add up is hardly worth it. I used the chevy because it was in a early chevy 4x4 truck, and staying chevy made the conversion easier and cheaper.
Dangit, I am starting to think that also, I just cant see spending $1500 on one that breaks the case so easily just slowly hauling a 10K trailer up and down long gravel hills (It was even in low range) :eek:

I would be into a NV4500 swap but it looks like by the time you get every thing its pretty easy to spend $3000-$5000 on getting a $3500 "spare" truck going again. :(
 

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Wazz, you called the shop the other day didn't you? How bad is the 727 you have? I know we talked about all kinds of options, but reading this thread made me realize you're really after the simplest, cheapest fix for your farm truck.

If your 727's in 3 pieces it may be hopeless, but we weld cases and bellhousings back together regularly. We could piece what you have back together and fix it so it won't happen again.
 

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Have you thought about the possibility that you could have another issue causing the breakage? I know that if you have engine or tranny mount issues you can put undo torque on the case and split it. Not the case, but in race car situations you can not solid mount the engine and tranny because frame twist will snap it. Bad example, but you get the picture. Perhaps you have failed mounts or a drive shaft issue causing abnormal vibration?

Just some thoughts since case breakage should not be a repeat issue in a truck that is not fueled up.

Thank you for the replys and information!




Nope I am open for most any option, the THM400 was from a Small Block, but yeah both of your replys made me start thinking about the shifting points of gas v/s diesel, even though they are tuneable under the vaccume hose on the modulator for cars, the diesel one is most likely not adjustable. humm.

I did check into a 727 bought out right as a complete unit and I just have a hard time swallowing $1500 for a 3spd Auto, especialy after destroying this one in less than 120 miles on its trip of me owning the truck, (this 727 was also rebuilt less than 10K miles ago).

I have bought 3 dodge rigs in the last 2 years and all 3 have poped transmissions (2004.5 Cummins is on its 4th transmission in 60500 miles, 79 440 Motorhome 727, and now this 1990 CTD 727), my luck with Dodge transmissions is not been a good experiance so far.








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Dangit, I am starting to think that also, I just cant see spending $1500 on one that breaks the case so easily just slowly hauling a 10K trailer up and down long gravel hills (It was even in low range) :eek:

I would be into a NV4500 swap but it looks like by the time you get every thing its pretty easy to spend $3000-$5000 on getting a $3500 "spare" truck going again. :(
 
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