Adapter and spline count for Ford 4R75 auto trans. to NP273F TC

[McGuyver]

Looking to convert my 2009 Ford E350 van to 4wd. Looking on information for where I can get the adapter kit for the rear of the transmission. I have a 5.4 L with 4R75 transmission. Also would like to know what spline count that transmission has so I know which version of the NP273F to get. Apparently there were several different spline count versions used throughout the years, as this page indicates.

Fullsize Ford Truck Transfer Cases – Blue Oval Trucks

New Process (NP) 271 Transfer Case Looking for information on transfer cases found in fullsize Ford trucks? This page is dedicated to those cases and provides a list of vehicles, a list of cases that were found in them, and photos for reference.

www.blueovaltrucks.com

Thank you.

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[Raul]

You need to change the output shaft to a longer one (4x4 version and requires to gut out the transmission) ) and change the output tail for a double flange. These are the markings on my flange. You will have to drill and tap a hole on your transmission since the flange is for older version of the 4r75.

You may want to look at this post https://expeditionportal.com/forum/threads/2010-4r75e-2wd-to-4wd-help.193435/#post-2473937

And this is how I did the drilling on the Transmission. https://expeditionportal.com/forum/...0-5-4-diy-coil-conversion.167666/post-2674736

 

[broncobowsher]

Get a 4WD version of a 4R70W. You rob the output shaft and tail housing off it. Output shaft change requires a complete teardown of your 4R75W. The output shaft is literally the first part installed in the case when you start rebuilding it. The part that sticks out the back and is installed in the transmission from the front. The 4R70W parts are easier to find and for what you need they are the same. The 75 has harder gears for a higher torque capacity.

It's a mix and match of common stock parts. If you talk to your local transmission rebuilder they might even have the parts laying around.

 

[McGuyver]

Thanks guys. I've done this conversion once before on a Chrysler 727 auto transmission, so I know what to expect. Except on that conversion, the 4wd output shaft was shorter than the 2wd version, so I'm surprised to hear that it's longer with this transmission.

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[McGuyver]

So back to one of my original questions, does anyone know what the spline count is supposed to be?

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[broncobowsher]

31 spline

 

[McGuyver]

Thank you.
So according to this page, I could get an NP273F form a 2000 - 2005 Ford Excursion with a speedometer hole, or I could get an NP273 from a 2000 - 2003 Ford F-series SuperDuty without the speedo hole (however my 4R75 is a four speed, and this page says the SD version of the TC is for a five speed)

Fullsize Ford Truck Transfer Cases – Blue Oval Trucks

New Process (NP) 271 Transfer Case Looking for information on transfer cases found in fullsize Ford trucks? This page is dedicated to those cases and provides a list of vehicles, a list of cases that were found in them, and photos for reference.

www.blueovaltrucks.com

Honestly, I'm not sure which one I need. Any ideas?

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[skumancer]

Thank you.
So according to this page, I could get an NP273F form a 2000 - 2005 Ford Excursion with a speedometer hole, or I could get an NP273 from a 2000 - 2003 Ford F-series SuperDuty without the speedo hole (however my 4R75 is a four speed, and this page says the SD version of the TC is for a five speed)

Fullsize Ford Truck Transfer Cases – Blue Oval Trucks

New Process (NP) 271 Transfer Case Looking for information on transfer cases found in fullsize Ford trucks? This page is dedicated to those cases and provides a list of vehicles, a list of cases that were found in them, and photos for reference.

www.blueovaltrucks.com

Honestly, I'm not sure which one I need. Any ideas?

Sent from my SM-G973U using Tapatalk

Were you able to figure this out? I'm on the same boat, I need to figure out Spline Count of the 4R75E 4WD output shaft to get the right transfer case. I also want to know if the indicated TC works even though it says it's for a 5-speed (I see no issue, it should mate, they are mechanical devices in the end).

 

[malcolmzilla]

What t-case did Ford put in the F150 of similar vintage? Should work with the 4r75 with 4wd output.
I have a BW 1356 behind my 4R75 in my 06 Clydesdale - I didn't assemble it however, only pulled it to reman the transmission.

 

[McGuyver]

Were you able to figure this out? I'm on the same boat, I need to figure out Spline Count of the 4R75E 4WD output shaft to get the right transfer case. I also want to know if the indicated TC works even though it says it's for a 5-speed (I see no issue, it should mate, they are mechanical devices in the end).

I had to put this project on hold for about a year and a half while I worked on other more pressing matters. I'm just now getting back to it. Right now I am working on rebuilding/regearing front Dana super 60, and rear Sterling 10.5 to use 4.56 gears. I will start looking into the transmission/TC question more once I get the axles done. I did however come across this web page recently that indicates it probably uses either a 31 or 34 spline output:

Automatic Transmissions and Transmission Parts. 3 Year Warranty and Free Converter

www.transdepot.net

Edit: I forgot to mention, I decided to switch to an NP271F for sake of simplicity.
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[skumancer]

I had to put this project on hold for about a year and a half while I worked on other more pressing matters. I'm just now getting back to it. Right now I am working on rebuilding/regearing front Dana super 60, and rear Sterling 10.5 to use 4.56 gears. I will start looking into the transmission/TC question more once I get the axles done. I did however come across this web page recently that indicates it probably uses either a 31 or 34 spline output:

Automatic Transmissions and Transmission Parts. 3 Year Warranty and Free Converter

www.transdepot.net

Edit: I forgot to mention, I decided to switch to an NP271F for sake of simplicity.
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I ended up getting a 31-spline output shaft, only one I could find easily, and got a BW1356 T-case out of an F150 from 1996. Transmission has been completely rebuilt, new torque converter, and replaced output shaft (shorter, 31-spline). Got the adapter at the end of the transmission to accept a transfer case. When I get the van back, I’ll rebuild the T-case, but I already did an initial check on it and it looks good.