issues after 6L80 swap from 2011 to 2008 gmc 1500

[swinn467]

my buddy blew up his 4l60 on my 2008 gmc 1500 and bought a 2011 gmc parts truck that (unknown to me at the time) had a 6l80 in it. Using the newer E38 computer, wiring harness, gauge cluster, and shifter to work with the 6l80 we got it all back together, the truck will run and drive for a sort period of time then go into reduced power mode for what seems like no reason. The TCS/stabilitrac/ABS and check engine lights are on and there is also an odd code for the steering wheel---

---0x543: C0055 - Steering Wheel Position Sensor Signal D (SES, Current, History)---


The trans will shift through all the gears fine and everything appears to be working correctly until it goes into the limp mode.

First swap like this, any help is appreciated

[dhoagland]

I'm wondering if you need to Flash your ABS and BCM with an updated flash file that matches your E38 ECM
(And honestly this is a total guess, I'm not sure what modules you have vs what was in the donor truck)

[IARLLC]

Possible that the steering position sensor got damaged during the shifter replacement.

Also agree about flashing the BCM at least. Since tap up/tap down runs through it on 6L80E systems.

Honestly, seems strange to me that you are only getting that 1 code.