I have a 1999 K2500 (OBS) that had a tired 454 in it. I recently acquired an 8.1L out of a 2001 Silverado (NBS). The donor truck was 2WD and had the Allison transmission. I did not get the transmission because my truck is 4wd and I have read what a PITA it is to put an Allison in one of these older trucks. I decided to just use my 4L80E. I have installed the engine in my '99 and bolted it up to the 4L80E. I was able to locate all of the necessary brackets to mount the accessories in the proper place. I was fortunate enough (I think) to located a wiring harness from a 2001 C3500 (OBS) which of course was 2wd. Everything plugs in just like it was made for this truck and engine combo. I want drive by cable so I am using the 454 throttle body. I was able to remove the IAC and TPS plugs from the 454 harness amd know where they need to connect to the ECM. The last thing I need to figure out is how to wire the 4wd 4L80E and transfer case. The C3500 harness has plugs for the Neutral Safety Switch on the side of the transmission but I have one remaining 4 wire plug that I have not yet figured out. The 4 wires on the truck side one goes to a sensor on top of the transfer case (I think range selector), two go to the 4wd actuator up front, and the 4th i have not been able to track down.
Are there any transmission experts in the group or anyone who can point me in the direction of a good wiring diagram? I have raced the wires through the old 454 harness and they terminate as follows;
Pin A - goes to pin #23 in black ecm connection (old harness)
Pins B&C - both black wires, appear to be ground. One ties into another ground wire about half way up the harness and the other goes to the plug on the firewall and connects to D6. Unfortunately I don't know which one is goes where.
Pin D - Also goes to firewall plug pin E5.
Any help would be greatly appreciated.
Are there any transmission experts in the group or anyone who can point me in the direction of a good wiring diagram? I have raced the wires through the old 454 harness and they terminate as follows;
Pin A - goes to pin #23 in black ecm connection (old harness)
Pins B&C - both black wires, appear to be ground. One ties into another ground wire about half way up the harness and the other goes to the plug on the firewall and connects to D6. Unfortunately I don't know which one is goes where.
Pin D - Also goes to firewall plug pin E5.
Any help would be greatly appreciated.
