Preface: I have a 2002 Jeep Wrangler that was swapped with a L83/6L90e from a 2015 Silverado. The original NP231 Tcase is in the Jeep. The speedometer and shift points are good in 2WD and 4HI. I did not do the swap, just working out issues for the owner.
The problem: 4Low is not great. Shifting sucks and even in manual mode some shifts are denied.
What I have discovered: The RPO for the VIN/OS shows a NQG T-case (manual shift t-case). Schematic shows speed sensor coming from T-case and going to ECM X2 pins 6 and 7. I have an empty spot in Pin 6. Looking at the 6L90e schematic, it shows Pin 8 is used for non- NQG (and if I'm reading it correctly only for 2WD vehicles). I do have a wire in Pin 8, but I have not confirmed it is my VSS. The calibration says VSS is 36 Pulse/Rev. The Jeep NP231 shows it is a 8 Pulse/Rev. The calibration also has a selection for where the VSS is located.
Question:
Can I wire the Jeep NP231 speed sensor to the correct Pin (6)?
Will I need to change the OSS/TOS tab to enabled? ([ECM] 14025 - OSS/TOS Physically Connected: OSS/TOS sensor is physically connected to the ECM (manual transmission, etc)
What is TOS electrical interface? It says value 0-16, and currently at 4. ([ECM] 14027 - TOS Electrical Interface: Indicates which TOS interface has the TOS sensor attached to it.)
Can I just change the VSS to 8 Pulse/Rev?
Also, I did find that the ECM has a ground switch input to signal 4Low. Since I found no other inputs telling the TCM that it is in 4Low, would it be safe to assume that this input will tell the trans to change to 4Low shift schedule?
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