Sponsored

Selec-Trac Transfer Case Swap - Myth Busted

DC3

Well-Known Member
First Name
Carl
Joined
Jul 14, 2020
Threads
42
Messages
319
Reaction score
850
Location
Willmar, MN
Website
dilabs.cc
Vehicle(s)
'21 JT GDE Ecodiesel, 22 Polestar 2
Occupation
engineer
There have been many questions, rumors, and opinions on whether or not the Selec-Trac transfer case could be swapped into a part-time configured Jeep. I set out to answer the question.

Initially, I thought I could swap the transmission wiring harness, the Transfer case control module and reprogram the BCU. But after many hours of wiring harness comparison, and shop manual review, I have come to find the dash and body wiring harnesses do not have the leads for the transfer case stepper motor control. The harnesses aren't that expensive and I have contemplated swapping them but have since decided against the effort. Then I thought about building an 8 wire loom to bridge the gap but decided against that too.

My Gladiator is an early 2020 build, perhaps the later builds have the provisions built-in but I doubt it.

For those who want the Selec-Trac, buy a Gladiator with it!

I am happy to share more details of my findings for those who are curious or want to pick up where I left off.
Sponsored

 

81Mojave

Well-Known Member
First Name
Matt
Joined
Jun 26, 2021
Threads
5
Messages
152
Reaction score
99
Location
PA
Vehicle(s)
2021 Mojave, 2010 JKU
Occupation
Transportation
Interesting…
Do you think the axles are interchangeable?
 
OP
OP
DC3

DC3

Well-Known Member
First Name
Carl
Joined
Jul 14, 2020
Threads
42
Messages
319
Reaction score
850
Location
Willmar, MN
Website
dilabs.cc
Vehicle(s)
'21 JT GDE Ecodiesel, 22 Polestar 2
Occupation
engineer
Interesting…
Do you think the axles are interchangeable?
Yes. I installed the CV axles and they fit like a charm. Just make sure you get the right length (for you the wide track D44).

I am glad I swapped the axles, no more binding in 4x4.
 

Mac

Well-Known Member
Joined
Nov 30, 2017
Threads
33
Messages
2,156
Reaction score
2,301
Location
MA
Vehicle(s)
2020 JT Hydro Blue Max Tow
Yes. I installed the CV axles and they fit like a charm. Just make sure you get the right length (for you the wide track D44).

I am glad I swapped the axles, no more binding in 4x4.
What did it cost to swap the axles?
 
OP
OP
DC3

DC3

Well-Known Member
First Name
Carl
Joined
Jul 14, 2020
Threads
42
Messages
319
Reaction score
850
Location
Willmar, MN
Website
dilabs.cc
Vehicle(s)
'21 JT GDE Ecodiesel, 22 Polestar 2
Occupation
engineer
What did it cost to swap the axles?
$500 - $800 depending on whether you swap with factory or aftermarket OE. I wasn't able to find the Mopar passenger axle so I went aftermarket. No significant differences in quality or workmanship except the aftermarket boot would not fit through the steering knuckle without removing the clamp.

The factory clamps are welded whereas the aftermarket are standard CV clamps. I removed the CV clamp and installed a new clamp after it was through the knuckle. That was easier than removing the knuckle. If you did all aftermarket you might be in the $300 - $400 range
 

Sponsored

DAVECS1

Well-Known Member
First Name
David
Joined
Jan 24, 2020
Threads
56
Messages
1,861
Reaction score
2,515
Location
Peoria, IL
Vehicle(s)
2020 Gladiator Sport S Max Tow
Well thanks for the leg work. I assume the stepper motor is what is doing the shifting in and out of 4wd. In the "tune" there is no distinction between a 4 auto and regular transfer case. So my guess is that module does all the work.
 
  • Like
Reactions: DC3

Kevin_D

Well-Known Member
First Name
Kevin
Joined
Oct 18, 2020
Threads
50
Messages
2,328
Reaction score
3,074
Location
Inland Northwest
Vehicle(s)
2021 Sport S, 1971 J4000, a bunch of other stuff
If there’s a stepper motor doing the shifting, why is the transfer case shift lever such a bitch to shift?

Kevin
 
OP
OP
DC3

DC3

Well-Known Member
First Name
Carl
Joined
Jul 14, 2020
Threads
42
Messages
319
Reaction score
850
Location
Willmar, MN
Website
dilabs.cc
Vehicle(s)
'21 JT GDE Ecodiesel, 22 Polestar 2
Occupation
engineer
The stepper motor is what modulates the clutch or friction plates when the transfer case is in 4 auto. It's a bit of a misnomer as a shifter but that's the terminology the wiring diagram uses. Or perhaps there is a secondary shifter in the Selec-trac trans case?
 

DAVECS1

Well-Known Member
First Name
David
Joined
Jan 24, 2020
Threads
56
Messages
1,861
Reaction score
2,515
Location
Peoria, IL
Vehicle(s)
2020 Gladiator Sport S Max Tow
The stepper motor is what modulates the clutch or friction plates when the transfer case is in 4 auto. It's a bit of a misnomer as a shifter but that's the terminology the wiring diagram uses. Or perhaps there is a secondary shifter in the Selec-trac trans case?
That is what I figured. I am surprised it does not have its own harness to the module. Hmmm business opportunity??
 
OP
OP
DC3

DC3

Well-Known Member
First Name
Carl
Joined
Jul 14, 2020
Threads
42
Messages
319
Reaction score
850
Location
Willmar, MN
Website
dilabs.cc
Vehicle(s)
'21 JT GDE Ecodiesel, 22 Polestar 2
Occupation
engineer
That is what I figured. I am surprised it does not have its own harness to the module. Hmmm business opportunity??
Seriously, get out of my head 🤣🤣.

I started searching for the terminals this morning to create a harness. I figure at this point I have all the other components I need.....however the last thing I need is another pet project but we'll see where this goes.
 

Sponsored

81Mojave

Well-Known Member
First Name
Matt
Joined
Jun 26, 2021
Threads
5
Messages
152
Reaction score
99
Location
PA
Vehicle(s)
2021 Mojave, 2010 JKU
Occupation
Transportation
Thank you, interesting info!!!
 

GladiatorAdventureBound

Well-Known Member
First Name
Adam
Joined
Apr 24, 2020
Threads
12
Messages
104
Reaction score
39
Location
Saint George
Vehicle(s)
2020 Gladiator Sport
$500 - $800 depending on whether you swap with factory or aftermarket OE. I wasn't able to find the Mopar passenger axle so I went aftermarket. No significant differences in quality or workmanship except the aftermarket boot would not fit through the steering knuckle without removing the clamp.

The factory clamps are welded whereas the aftermarket are standard CV clamps. I removed the CV clamp and installed a new clamp after it was through the knuckle. That was easier than removing the knuckle. If you did all aftermarket you might be in the $300 - $400 range
Do you have part numbers by chance?
 

tommyp

Well-Known Member
Joined
Sep 24, 2020
Threads
5
Messages
137
Reaction score
101
Location
VT
Vehicle(s)
2021 Sport S Max Tow
Interesting. Any Idea if it would be easy to go the other way? normal tcase in a select trac?
 

TwelveGaugeSage

Well-Known Member
First Name
Jason
Joined
Aug 17, 2021
Threads
4
Messages
281
Reaction score
411
Location
Massuhtwoshits
Vehicle(s)
2017 Kawasaki Z125, 2016 Yamaha WR250R, 2021 JTR
Occupation
Air Force Contractor
What are your thoughts on why it isn't available with the manual transmission? I've heard a few theories, but you seem more mechanically inclined than most.
 
OP
OP
DC3

DC3

Well-Known Member
First Name
Carl
Joined
Jul 14, 2020
Threads
42
Messages
319
Reaction score
850
Location
Willmar, MN
Website
dilabs.cc
Vehicle(s)
'21 JT GDE Ecodiesel, 22 Polestar 2
Occupation
engineer
Do you have part numbers by chance?

These are the non-wide track cv shaft part numbers:

68403881AAAxle Shaft, Left
68394142AA Axle Shaft, right

These will not work with a Mojave, Rubicon, or max tow.
Sponsored

 
 



Top