4L80 PCM and Wiring Harness Info

[Beetle]

I have looked for about 2 days and getting a ton of info from here and ls1 tech and other websites but I cannot find a direct answer that will point me in the direction I need to go. This summer I am going to do a 4.8/5.3/6.0 swap in my stepper, I don't care what engine so long as I have one of those. I am going to boost whatever it is I get so I want a 4L80 (I know 6.0s have em already) to bolt up behind it. fleaBay has tons of these trans but not one seems to come with the controller. What did you guys do for a controller and wiring? Where do I buy said controller or harness? Thanks for any help.

[MalibuSSwagon]

If you are using the stock PCM it will control the 4L80E with the correct programming. You just need to either repin the 4L60E connector for the 4L80E or use the factory harness.

[Beetle]

Originally Posted by MalibuSSwagon

If you are using the stock PCM it will control the 4L80E with the correct programming. You just need to either repin the 4L60E connector for the 4L80E or use the factory harness.

Like I said, where do I get the PCM? What do you mean by factroy harness? Most if not all trans from eBay or JY do not seem to have a harness with them...

[BR3W CITY]

I think you might have misunderstood some of what you were reading. Some of that is concerning running a 4l80e in a setup that can't normally run one (carb, aftermarket efi, behind a non ls motor, attached to a baked potato)

When you get a harness made, you specify that you want to run a 4l80e. The branch of transmission sensors wires off of the main engine wiring harness. You don't need a stand alone harness group unless your running an aftermarket TCM controller (which you won't be doing). You can have a stock junkyard harness reworked from 4l6oe to 4l80e, the primary difference being an additional VSS (ISS) sensor.

Where exactly you get the ECM is up to whatever works for you. If you use car-part.com you can see what local yards near you have. If you still haven't found the engine yet, this WHOLE discussion is a moot point. If you find an engine/trans combo with the ECM (which is ideal) then it will ALL work together.

IF you end up needing to piece the setup together, then the important thing is finding an ECM from the same vehicle and setup. What I mean is; if you have a 2003 engine, then you want to find a 2003 ECM from a truck with a v8/auto. This is pretty easy to find, and will be CRUCIAL if you are running a DBW setup. DBW is simple to hook up, so long as you just get everything from a matching vehicle.

Like I said, I think your tripping over yourself just a bit. Its a ton of cool stuff, and a ton to read, but if you burn yourself out the project will just become a headache (for all of us )

Now if you find an engine thats very very new, or want to run an oddball combo, then there is a bit more to work on...but we'll cross that bridge if we get there. Deal?

[Beetle]

Thanks BR3W CITY

I am glad I found that car-part site. The local JY I frequent has some 5.3s listed for cheap. I will go later today and check out how complete they are. fleaBay has a fully dressed 5.3 intake to pan, all acc, wiring and ecm for $1,000 plus shipping.

Where I got confused is some people say that the trans is controlled by the ECM, some say it isnt, some say I need a PCM. So that is where the confusion was coming from. Sounds like you got me straight. Hopefully next month I will have a 5.3 sitting in my garage, then I will start lookin for a 4L80, then work on gas tank and just keep acquiring parts and research.

[gmech]

For the most part, gen3 ls motors are from 99-06. Gen4 is from 07 on for truck and vans. Gen4 will need a tcm for the transmission. Gen3 trans are controlled by the ECM. As far as I know.

[dayj1]

Originally Posted by Beetle

Where I got confused is some people say that the trans is controlled by the ECM, some say it isnt, some say I need a PCM.

Generally speaking, Gen 3 used a PCM (Powertrain Control Module). The PCM controls the engine and transmission.

Gen 4 used an ECM (Engine Control Module) and a separate TCM (Transmission Control Module).

People interchange PCM and ECM, but they are technically two different things.

[BR3W CITY]

ECM PCM PCU ECU its all the "damn computer" when it doesn't tune right.

[Custom 68]

from my understanding if you have the computer for the 5.3 and want to use the 4l80e then there is a few changes required in the computer more than just saying it is an automatic. I undestand a "segment" swap is required. That is no big deal to get done but it will need to be addressed then the computer will control the transmission.
I have a 4l80e I am going to swap into mine sometime over the summer I will just need to have this done and decide what spacers or flexplate I will need.