Gen III swap and 4 low (4WD 4L80E)
I have an 02 6.0L vortec out of a Yukon Denali (DBW) and a 4x4 4L80E, NP 241 transfer case behind it. The transmission is currently tuned for 2WD so it works great in 2 hi and 4WD hi, but the second 4 low is engaged it wont shift out of 1st unless manually shifted. The VSS is located in the transfer case. Since the gear ratios are different in 4low a 2WD tune isn't going to do me any good if I want full use of the transfer case. In the 4WD trucks of this year, the PCM looks for a ground signal on pin 16 in the red connector when 4WD low is engaged to shift properly. I will be running a switch on the manual shifter for the transfer case but I need a 4WD tune for my 4L80E. Anyone that is familiar with this issue have this file?
OK, I was just trying to give some background so let me rephrase the question. Does anyone have a 4L80E 4WD file?
for a 2002 drive by wire 6.0L 4L80E 4x4
First post here. I too am looking for the same file, 2002 6.0/4l80e/4wd. Swapped my 2002 2500hd from 2wd to 4wd, and experiencing same symptoms w/ 4lo. Everything else works great except for this. Searched the repository, found some 2wd files but no 4wd.
This stuff is all new to me, just purchased hptuners, haven't received it yet, should be here sometime next week. Mine is not DBW, don't know if those files are different?
I have the PCM out of the donor truck that I took all the 4wd stuff from but it is a 2000 model.
From searching and reading it sounds like I want a 01-02 file because the PCM's are different from the 99-00?
From my understanding, a Tech II should be able to flash one of these files given a 4wd vin? I might be able to get access to one of these, but don't know if it will help me in this situation?
Lastly, I believe there is supposed to be a "4wd light" that comes on in the instrument cluster for the manual shift tcase when in 4wd. (Mine is a 261) This isn't a huge deal, but was wondering if this was controlled from the PCM as well. 4wd engages properly, (front axle is electronic) and I used the factory harness from the donor truck on mine. It could be that a bulb or something is missing from the cluster, haven't checked that far into it yet.
If anyone has any suggestions/comments/corrections in my assumptions it would be greatly appreciated.
Last edited by 1970lark; 04-28-2012 at 02:11 PM.
here you go. I know *nothing* about the tune, if it's stock or modified. This was in a PCM a customer sent me and I'm sure he had problems, because I reflashed his PCM with a TECHII.
Originally Posted by blackdog76
But the VIN is a correct VIN. Try it. If it doesn't work, take it to the dealer and have them rebuild the PCM using that VIN. Because I'm not sure if the program was wrong application or?