Np243 manual shift

DonYukon

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I converted a NP246 to a 241 Tcase. in my SAS yukon. Is the reason for the swap a SAS or just preference?
 

DonYukon

Dont stop until it sounds expensive
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Disclaimer Mine was a NP246 to NP241 (some of your steps may differ)

Either way you will obviously need the correct transfer case. the good news is the 241 and 243 both share the same spline counts so they will work with both 700r4 and 4l60 Trans. Just be sure to pick up a 27 spline for a 1500 as most 32 splines are for the 4l80E if memory serves me right.

the easy part is bolting it up honestly

On top of that you will have to do some wiring. reasons for this
The VSS on mine is a 3 pin vs NP241s 2 pin. This needs to be wired correctly so that your PCM will know the output speed of the case so shifting in different Ranges is possible. dont do this and you will have a very jerky slippy transmission lol NOT ADVISED

next you will have to pin out your TCCM so you can "trick" your ECM into thinking there is still a push button system when there is not. The TCCM also plays a crucial role in letting the PCM know its in Lo range and to alter the shift points in the transmission based off speed this is done by pinning out 3 wires on a single electronic switch Id have to take a look at a diagram to tell you but thats the short jist of it.

lastly youll need either a direct swap linkage or something custom like the one i used Highly reccomend if you want it in a custom console https://jb-custom-fabrication.myshopify.com/
 
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Disclaimer Mine was a NP246 to NP241 (some of your steps may differ)

Either way you will obviously need the correct transfer case. the good news is the 241 and 243 both share the same spline counts so they will work with both 700r4 and 4l60 Trans. Just be sure to pick up a 27 spline for a 1500 as most 32 splines are for the 4l80E if memory serves me right.

the easy part is bolting it up honestly

On top of that you will have to do some wiring. reasons for this
The VSS on mine is a 3 pin vs NP241s 2 pin. This needs to be wired correctly so that your PCM will know the output speed of the case so shifting in different Ranges is possible. dont do this and you will have a very jerky slippy transmission lol NOT ADVISED

next you will have to pin out your TCCM so you can "trick" your ECM into thinking there is still a push button system when there is not. The TCCM also plays a crucial role in letting the PCM know its in Lo range and to alter the shift points in the transmission based off speed this is done by pinning out 3 wires on a single electronic switch Id have to take a look at a diagram to tell you but thats the short jist of it.

lastly youll need either a direct swap linkage or something custom like the one i used Highly reccomend if you want it in a custom console https://jb-custom-fabrication.myshopify.com/
Thank you very much! The np241 I picked up actually had a 3 pin VSS sensor in it, so that’s a bonus! I think the only think I need to figure out is the wire to the TCCM. I pulled the carpet in the truck and already had the lights for the floor shift wired in. Once I put bulbs in them, they changed to show truck in 4WD. Hoping all else goes smooth. Probably doing the actual swap in a week or two. Thank you again for all your help!
 
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