HELP! Nv4500 Swap, so many transfer cases so little time.

[Preston Tucker]

Ive been looking on here for hours and could not find a thread with the information I need, maybe you all can help! Anything is appreciated.

I am converting my 1974 k25 from a burnt th350 to a Nv4500. I have all the hydro stuff for the cab out of an 87 parts rig and tonight I bought a whole 2000 k2500 with the tranny for 1000 dollars (has 120k on it). My question is what t case do I need? I did a ton of research and from what I gather I could use a 208 or a 205 as long as its 32 spline but i rather avoid the 208 because I want the bulletproof t case. I have recently discovered that there are short shaft and long shaft female 205s, which one do I need??

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I would post a picture of the squarebody but there isnt much to photograph currently... Hang in there!

 

[SquareRoot]

I've done this.... recently. 1st, there's nothing wrong with the 208 t-case, it's a good case. However, if your like me, you want the 205 for bragging rights if nothing else. Plus, you can twin stick for the ultimate cool factor. Additionally, you can make it a fixed output for extra dependability. If you break the rear shaft while 10 million miles out in the sticks you still have front wheel drive. Of course this will never happen but we think it's cool.

Now the 205 has a long and a short input shaft. Either one will work. The hard part is finding the later round, 6bolt pattern case. Buy whatever you find! Changing the shaft is easy. If you choose the long one it will require a 1-5/8 spacer (the difference between the short vs long shaft) between the trans and t-case. AA sells them.

The spacer will make the rear shaft shorter and the front shaft longer, which is a good thing.

As for a shifter, I highly suggest using the floor mount twin stick from ORD. It's bulletproof and badass.

Please get the pigtails off the donor truck the 4500 is coming out of for the reverse light switch and the neutral safety switch. I had to track them down and it was a PITA to find those small items.

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[Curt]

You can run dodge 205 as well.They came from factory with the combo.

A call to advanced adapters will help answer what will be you easier options.

The 208 is a good case.The front output is only in use in 4WD,so it will last a long time.It’s lighter by 70 lbs then the 205.It’s pretty strong by the fact it was used in 1 1/4 ton CUCV military trucks.

The 205 however is pure beef and will most likely outlast the truck and the next truck too.The aftermarket has more support for this case than any other.

For myself,I swapped the 208 out for the 205 for a fixed rear output and to get away from the aluminum case.The 208 was a smoother operator and easier to shift,lower low range.However,one rock will easily pierce the 208,but then again this is offroad mostly minded.

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[Preston Tucker]

I've done this.... recently. 1st, there's nothing wrong with the 208 t-case, it's a good case. However, if your like me, you want the 205 for bragging rights if nothing else. Plus, you can twin stick for the ultimate cool factor. Additionally, you can make it a fixed output for extra dependability. If you break the rear shaft while 10 million miles out in the sticks you still have front wheel drive. Of course this will never happen but we think it's cool.

Now the 205 has a long and a short input shaft. Either one will work. The hard part is finding the later round, 6bolt pattern case. Buy whatever you find! Changing the shaft is easy. If you choose the long one it will require a 1-5/8 spacer (the difference between the short vs long shaft) between the trans and t-case. AA sells them.

The spacer will make the rear shaft shorter and the front shaft longer, which is a good thing.

As for a shifter, I highly suggest using the floor mount twin stick from ORD. It's bulletproof and badass.

Please get the pigtails off the donor truck the 4500 is coming out of for the reverse light switch and the neutral safety switch. I had to track them down and it was a PITA to find those small items.

You must be registered for see images attach

Thank you very much for the info, and yes the 205 is mostly for cool factor! What else?? I already have a 208. Say I found a truck with a 205 6 bolt housing, willt he th400 or the sm465 have the short shaft? I rather avoid buying adapter kits and make it look like it belongs in the truck.

And yes screwing with little things, thats why i bought a whole truck and not just the tranny for 1400 dollars! Plus I know this one drives.

 

[SquareRoot]

Thank you very much for the info, and yes the 205 is mostly for cool factor! What else?? I already have a 208. Say I found a truck with a 205 6 bolt housing, willt he th400 or the sm465 have the short shaft? I rather avoid buying adapter kits and make it look like it belongs in the truck.

And yes screwing with little things, thats why i bought a whole truck and not just the tranny for 1400 dollars! Plus I know this one drives.

The th400 has several output shaft lengths but, if its a 4wd version it will fit any 4wd. Its the input shaft on the t-case that matters. The 208 has different input shafts as well. Not in terms of length but spline count. The ones behind th400 and nv4500 will be the correct 32 spline.

The "adapter" kit from AA is simply a solid aluminum spacer. If you don't use it then your front driveshaft will be shorter and the carden joint will wear faster. Remember, any truck that came with the 4500 had IFS and driveshaft angle was a non-issue. The 4500 will bolt directly to the t-case (round pattern) but with a 205 you have to notch the trans case (4wd Adapter) to clear the 205's shift rails.

 

[Curt]

After 85’ the 32spline TH 400 or Sm465 will fit the same round pattern 205.That is called the long snout 32spline 205.Check out Offroad Designs Tech 205 page.It had all kinds of info.

That 205 is a bit scarce,but still out there.

 

[Preston Tucker]

The th400 has several output shaft lengths but, if its a 4wd version it will fit any 4wd. Its the input shaft on the t-case that matters. The 208 has different input shafts as well. Not in terms of length but spline count. The ones behind th400 and nv4500 will be the correct 32 spline.

The "adapter" kit from AA is simply a solid aluminum spacer. If you don't use it then your front driveshaft will be shorter and the carden joint will wear faster. Remember, any truck that came with the 4500 had IFS and driveshaft angle was a non-issue. The 4500 will bolt directly to the t-case (round pattern) but with a 205 you have to notch the trans case (4wd Adapter) to clear the 205's shift rails.

https://www.advanceadapters.com/products/50-6911--gm-nv4500-4wd-to-gm-np205/ Is this the kit I would need?

 

[SquareRoot]

Yes. Or just the adapter if you plan on using a different shifter than the factory one.

https://www.polyperformance.com/adv...cgJY0g8qh34zyZOstTrlHZacnFuE6vvcaAlV-EALw_wcB

 

[Preston Tucker]

Yes. Or just the adapter if you plan on using a different shifter than the factory one.

https://www.polyperformance.com/adv...cgJY0g8qh34zyZOstTrlHZacnFuE6vvcaAlV-EALw_wcB

Thank you, twin sticks are cool but its a budget build so I will probably just use the stock shifter.

 

[SquareRoot]

Another tidbit to ponder: The 205 is HEAVY, much heavier than the aluminum 208 that came behind the NV4500. Most nv4500's have an aluminum 4wd adapter. Hanging a 205 off there is a little precarious but they do make cast iron adapters. I "think" that Dodge used the cast iron version, not sure about GM. There are aftermarket cast iron ones available as well.

I'm in the process of buying a cast iron version, just for piece of mind.

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[eskimomann209]

I didn’t see anything about the np241!

the 88,89 one has a mechanical speedo.
The 90,91 has a vss for a future LS swap!
They even sell SYE

I’m going to put one in my OBS
Have all the parts need to finish the other projects to get this one back under the knife

 

[Preston Tucker]

Another tidbit to ponder: The 205 is HEAVY, much heavier than the aluminum 208 that came behind the NV4500. Most nv4500's have an aluminum 4wd adapter. Hanging a 205 off there is a little precarious but they do make cast iron adapters. I "think" that Dodge used the cast iron version, not sure about GM. There are aftermarket cast iron ones available as well.

I'm in the process of buying a cast iron version, just for piece of mind.

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Thats really cool and defiantly something I will be looking into! I really dont want that to be my weak link and its only 125 bucks so you really cant so no, plus it will make your truck virtually bombproof....

 

[Preston Tucker]

I didn’t see anything about the np241!

the 88,89 one has a mechanical speedo.
The 90,91 has a vss for a future LS swap!
They even sell SYE

I’m going to put one in my OBS
Have all the parts need to finish the other projects to get this one back under the knife

I would go np241c but the castings are thin and are a chain drive and not gear to gear, plus in some cases they are even harder to find than the late model 205s. Most 241s are drivers side drop.

 

[Dutch Rutter]

When I'm able to do this swap. I was/am planning on sticking with my np208 and swapping out the input shaft with a 32 tooth from high impact. Mainly just for the simplicity of not having to screw with spacing things, speedo stuff, and relocating mounting points.

However, the second that 208 blows I'd be all over a twin stick np205. I would even be interested in adding a splitter after the TC just to add to all of the chaos.

 

[Preston Tucker]

Another tidbit to ponder: The 205 is HEAVY, much heavier than the aluminum 208 that came behind the NV4500. Most nv4500's have an aluminum 4wd adapter. Hanging a 205 off there is a little precarious but they do make cast iron adapters. I "think" that Dodge used the cast iron version, not sure about GM. There are aftermarket cast iron ones available as well.

I'm in the process of buying a cast iron version, just for piece of mind.

You must be registered for see images attach

do they have a cast iron one thats already notched that you know of? Cutting that cast it on will be a PITA, and i really want a clean look.