PCM/Wiring differences between LQ4 & 8.1
Thread Starter
Registered User
Joined: Sep 2016
Posts: 1
Likes: 0
PCM/Wiring differences between LQ4 & 8.1 Greetings folks, I have an LQ4 donor rig (2003 Denali) and have been waiting for an appropriate truck to transplant the engine into. Today I stumbled upon a clean 2001 Silverado HD2500 4x4 for dirt cheap (has a clapped out 8.1 w/ blown headgasket). I am wondering if dropping the complete LQ4 will be relatively plug and chug aside from motor mounts, coolant piping etc.. I have heard the harness is similar if not the same, but I am wondering which PCM would be less complicated to run with, and how much of a hassle it will be to get dialed in. The the new truck has an Allison 1000 5sp auto. I have access to an Autel Maxisys at work but I don't have any real knowledge with regards PCM tuning.
Thanks in advance
-Dan
Thanks in advance
-Dan
they both use the P59 pcm, but the sensors on the 8.1 are different. totally not a plug and play. you'll be chasing wires and repinning, to what degree I dont know.
i'm pretty sure you could swap in the trans control segment for the allison (or the engine segment for the 6.0)
could be a fun project! I think most guys with the 8.1/allison go the duramax route. a 6.0 with a turbo would turn some heads!
i'm pretty sure you could swap in the trans control segment for the allison (or the engine segment for the 6.0)
could be a fun project! I think most guys with the 8.1/allison go the duramax route. a 6.0 with a turbo would turn some heads!
I recently read a 2000 8.1 in a 4x4 suburban.
PCM was a P01
The throttle body looked identical to DBW Corvette LS1
In fact all the sensors, coils etc looked like LS1 stuff.
I didn't think the P59 came out until 2004?
PCM was a P01
The throttle body looked identical to DBW Corvette LS1
In fact all the sensors, coils etc looked like LS1 stuff.
I didn't think the P59 came out until 2004?
TBH, I am unsure when what pcm came out when.
The DBW L18's I have seen were all p59 computers, w/no IAC driver.
and again I have never looked closely at the sensor plugs except to note the cam and crank sensors where in different spots than a gen 3 or 4 ls truck motor.
The DBW L18's I have seen were all p59 computers, w/no IAC driver.
and again I have never looked closely at the sensor plugs except to note the cam and crank sensors where in different spots than a gen 3 or 4 ls truck motor.
