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Successful NP273 to NP271 swap and everything works as it should.

7392 Views 15 Replies 8 Participants Last post by  Colebj93
Long story, short:
I have successfully swapped my ESOF NP273 tcase for a manual shift NP271 into my 06 Ram 3500 Mega Cab 4x4.

I have no CEL, I have no "service 4x4" light, and when I shift into 4hi and 4lo the "4x4" light illuminates on the dash.

Short story, long:

This project has been on the back burner for me for quite some time. I've seen a lot of other people successfully swap a manual tcase into their truck. You simply install a NP271, add some linkage and you're good, however, I had never seen a swap turn out like it should from the factory.

I had no need for it actually but when my dad's 07 Mega Cab started acting up, I knew it was time. His would shift into 4lo, 4hi, N all on its own, even with the truck off. I never wanted that to happen to mine and leave me stranded so me being the tinkerer of the two of us, I decided to just send it.

I ordered a rebuilt NP271D with a 2 position selector cam from Transfer Case Express out of North Carolina. It was delivered in 3 days in a very stout plastic container with included return label.

Install was easy.
Take out old, install new, fabricate linkage, wham bam, thank you ma'am.
(if you guys would like details on my linkage setup, I can include them later if there's interest)
But that's not why you're here.

In order to have an OEM setup I needed a program called AlfaOBD and an OBD2 Bluetooth dongle from Amazon.
(dongle)

If you're not familiar with AlfaOBD, it allows you to alter many different functions your truck's TIPM.
This can be risky so be careful and save a backup.
Really all I needed to do was tell the TIPM that instead of having 273 tcase, I now have a 271_2.
That '2' is very important.

For the 271 transfer case there is a 5 position and a 2 position sensor switch on top of the transfer case. This tells the TIPM whether or the tcase is in 2hi, 4hi, 4lo or N.
The 5 position is for the Power Wagons and I believe the gas powered trucks with full time 4wd.
(I tried to wire in a 5 position and it did not work)
The diesels only need a 2 position switch, this is critical. When you order your tcase, make sure you order a 2 position tcase.

Back to AlfaOBD,
When you're in the app you'll need to select your truck and then select the "body computer" and then the correct year range.
924549

You'll then be presented with another screen to connect to the CANBUS network. Once you're connected, there will be some tabs at the bottom right (at least on my android phone), select the one with a picture of a car.
924551

Select the drop down menu at the top, scroll down to "Car Configuration Change"
924552


Then in the new drop down menu at the bottom of the screen, scroll to Tcase type
924554


Then select "271_2"
924555


Select "start" then "next", wait for it to say "procedure completed".

Now, disconnect your batteries to reset the TIPM and you're set.

Once you wire in a 2 position switch to D201 on your tcase motor wiring (white with green tracer) and a ground...



...with this pigtail...


...you'll have a manual tcase with no CEL, and no service 4x4 light.


I know this is lengthy, so if there's any questions do not hesitate to ask. There's a lot more details I could get into but it's been a long day and need a beer.
Cheers馃嵒
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Pics for your viewing pleasure.
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Nice write-up. TY
Little update.
The solid rod end linkage you see in the picture gave me an existential crisis.

The direct connection makes any noise from the drivetrain travel through the shifter and into the cab, made me think my valves were toast.
Held the shifter with my hand and the noise went away.

Just so you guys are aware.
Great write-up. I did the same swap last month without the help of this thread. The only thing I did different was use the connector off of the old shift drive motor from the electronic transfer case. I had to destroy the motor-drive, but was able to then use this connector to wire directly to the two wire "4WD" position switch wiring without cutting my factory harness.
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Great write-up. I did the same swap last month without the help of this thread. The only thing I did different was use the connector off of the old shift drive motor from the electronic transfer case. I had to destroy the motor-drive, but was able to then use this connector to wire directly to the two wire "4WD" position switch wiring without cutting my factory harness. View attachment 928268 View attachment 928269

I am currently doing the same on my 03 2500. Would you mind sharing which two pins on the factory harness I would need to plug into to make the 2-pin switch on the 271 work with my factory harness? Thank You in advance.

This is another post I made. It should help you out. Let me know if you need anything else.
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Thanks for the reply @ID10Tpig. Im actually curious how @gpgofast got his to work without the OBD2. Wanting to know which two wires he had to tie in the harness to make it work. Hoping to not need the programmer but will get it if I absloutely have to.
Thanks for the reply @ID10Tpig. Im actually curious how @gpgofast got his to work without the OBD2. Wanting to know which two wires he had to tie in the harness to make it work. Hoping to not need the programmer but will get it if I absloutely have to.
I DID have to go into the BCM with AlfaOBD to change the transfer case type. The wires I spliced I believe are WT/DGN (White-Dark Green) and VT/YLW (Violet - Yellow).
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@gpgofast ok thanks for the quick response. Guess to make my 鈥4wd service鈥 light off I鈥檒l have to do some programming. Thanks again @ID10Tpig for the previous info.
Well I looked into the AlphaOBD and their website says they only work 0n 05+ trucks so I think I'm out of luck on my 03. I know the 04.5+ trucks have a different TIPM/ECM design so maybe that's why. Hopefully I can find another workaround.
Well I looked into the AlphaOBD and their website says they only work 0n 05+ trucks so I think I'm out of luck on my 03. I know the 04.5+ trucks have a different TIPM/ECM design so maybe that's why. Hopefully I can find another workaround.
Did you figure this out? I鈥檝e also got an 03 and want to manual swap with my current 273 if 4 low will work but will use the 271 if not.
Did you figure this out? I鈥檝e also got an 03 and want to manual swap with my current 273 if 4 low will work but will use the 271 if not.
Not sure if you got around to doing anything with yours yet, but I'm thinking with your older style 273, you could get away with the Ford kit that I found on Ebay. I also found a thread with details.


I wasn't quite so lucky to find a kit for the newer one in my '09 since they changed the shift cam design to a splined shaft, but I still managed just fine. I ended up removing the center gear and position switch from the actuator, cut a piece out of the cover, and welded a shortened 14mm wrench to the gear where the switch used to be. I also bent the box end to get it straight, and did a bit of grinding to make it thin enough for the bushing to fit.

All gears function correctly, and I actually have a defined neutral, unlike others had mentioned in the thread. I guess there's a notch for it in the new style cam. I used AlfaOBD to get rid of the SERV 4x4 light. I did run into a slight issue though... Since I removed the switch, I tried to program it like a 2wd truck by setting the "Tcase Type" to "Not Present", but it wouldn't take for some reason. I ended up changing it to 271_2 and that took care of the warning light.

One anomaly to point out is with the wrench pointing up, the shift pattern is exactly opposite of what the shifter says. No big deal to push the stick forward for 4x4 and all the way back for 4low. I could easily get the correct pattern by having it point down and lengthening the rod to reach. I could also get the indicator switch to work by leaving it in place, and welding something to the gear itself. Perhaps, I'll give it a go, if I come across another dead actuator to butcher. For now, my hack job will do.

Grey Bag Gas Trigger Gun barrel


Automotive tire Motor vehicle Hood Automotive exterior Bumper
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I reached out the manufacturer of the kit you referenced and he said it would not work on a Dodge transfer case. I like your ingenuity in solving your shifter problem.
Did you ever get the dash lights to work with the 271-2 programing and welding to the gear to keep location sensor? Im am trying to something like this now but would like the dash lights to work. I am putting in FMVB so i need to go with manual transfercase. i may change out shifter mechanism in my 273D so i can bolt on a factory lever. I would have to drill and tap the case of the two wire sensor since mine does not have it.

Not sure if you got around to doing anything with yours yet, but I'm thinking with your older style 273, you could get away with the Ford kit that I found on Ebay. I also found a thread with details.


I wasn't quite so lucky to find a kit for the newer one in my '09 since they changed the shift cam design to a splined shaft, but I still managed just fine. I ended up removing the center gear and position switch from the actuator, cut a piece out of the cover, and welded a shortened 14mm wrench to the gear where the switch used to be. I also bent the box end to get it straight, and did a bit of grinding to make it thin enough for the bushing to fit.

All gears function correctly, and I actually have a defined neutral, unlike others had mentioned in the thread. I guess there's a notch for it in the new style cam. I used AlfaOBD to get rid of the SERV 4x4 light. I did run into a slight issue though... Since I removed the switch, I tried to program it like a 2wd truck by setting the "Tcase Type" to "Not Present", but it wouldn't take for some reason. I ended up changing it to 271_2 and that took care of the warning light.

One anomaly to point out is with the wrench pointing up, the shift pattern is exactly opposite of what the shifter says. No big deal to push the stick forward for 4x4 and all the way back for 4low. I could easily get the correct pattern by having it point down and lengthening the rod to reach. I could also get the indicator switch to work by leaving it in place, and welding something to the gear itself. Perhaps, I'll give it a go, if I come across another dead actuator to butcher. For now, my hack job will do.

View attachment 973938

View attachment 973939
Long story, short:
I have successfully swapped my ESOF NP273 tcase for a manual shift NP271 into my 06 Ram 3500 Mega Cab 4x4.

I have no CEL, I have no "service 4x4" light, and when I shift into 4hi and 4lo the "4x4" light illuminates on the dash.

Short story, long:

This project has been on the back burner for me for quite some time. I've seen a lot of other people successfully swap a manual tcase into their truck. You simply install a NP271, add some linkage and you're good, however, I had never seen a swap turn out like it should from the factory.

I had no need for it actually but when my dad's 07 Mega Cab started acting up, I knew it was time. His would shift into 4lo, 4hi, N all on its own, even with the truck off. I never wanted that to happen to mine and leave me stranded so me being the tinkerer of the two of us, I decided to just send it.

I ordered a rebuilt NP271D with a 2 position selector cam from Transfer Case Express out of North Carolina. It was delivered in 3 days in a very stout plastic container with included return label.

Install was easy.
Take out old, install new, fabricate linkage, wham bam, thank you ma'am.
(if you guys would like details on my linkage setup, I can include them later if there's interest)
But that's not why you're here.

In order to have an OEM setup I needed a program called AlfaOBD and an OBD2 Bluetooth dongle from Amazon.
(dongle)

If you're not familiar with AlfaOBD, it allows you to alter many different functions your truck's TIPM.
This can be risky so be careful and save a backup.
Really all I needed to do was tell the TIPM that instead of having 273 tcase, I now have a 271_2.
That '2' is very important.

For the 271 transfer case there is a 5 position and a 2 position sensor switch on top of the transfer case. This tells the TIPM whether or the tcase is in 2hi, 4hi, 4lo or N.
The 5 position is for the Power Wagons and I believe the gas powered trucks with full time 4wd.
(I tried to wire in a 5 position and it did not work)
The diesels only need a 2 position switch, this is critical. When you order your tcase, make sure you order a 2 position tcase.

Back to AlfaOBD,
When you're in the app you'll need to select your truck and then select the "body computer" and then the correct year range.
View attachment 924549
You'll then be presented with another screen to connect to the CANBUS network. Once you're connected, there will be some tabs at the bottom right (at least on my android phone), select the one with a picture of a car.
View attachment 924551
Select the drop down menu at the top, scroll down to "Car Configuration Change"
View attachment 924552

Then in the new drop down menu at the bottom of the screen, scroll to Tcase type
View attachment 924554

Then select "271_2"
View attachment 924555

Select "start" then "next", wait for it to say "procedure completed".

Now, disconnect your batteries to reset the TIPM and you're set.

Once you wire in a 2 position switch to D201 on your tcase motor wiring (white with green tracer) and a ground...



...with this pigtail...


...you'll have a manual tcase with no CEL, and no service 4x4 light.


I know this is lengthy, so if there's any questions do not hesitate to ask. There's a lot more details I could get into but it's been a long day and need a beer.
Cheers馃嵒
You talked about the linkage, can I just use the stock linkage from a stock truck? I鈥檇 have to find a new one but that鈥檚 not a big deal. Thanks for the write up!
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