4L80e year model differences

[Critter]

I am curious about 2 things.

1. What year did the 4L80e go from the standard 6 bolt bell housing to the LS style 7 Bolt. I'm thinking it is as simple as if it was behind an LS then its 7, if it was behind a sbc/bbc then it is 6 bolt, correct?

2. Most importantly, is there a difference in in the wiring connections from a 91 model to an 07 model. The reason I ask is I have a 6.0 with wiring and computer from an 06 that was set up for a 4L80e and I want to know what years are a "plug and play". Do I need to stick to a 1999-2007 transmission, or would an older mid 90s model plug right up without any rewiring? As far as I can tell the only difference is the VSS being removed from the later model 4x4, but in the sense of the 2wd, would they all be the same???

[Shon]

The LSx are 7bolts. and there is wiring difference and some other differences in the tailshaft housing between different models.
Just have to make sure the PCM you are using is for a 4l80e, if not, then you need to rewire it.
now as for as using the older one, i dont know, i normally just buy the whole take out or run a Th350/400....

[Critter]

Thats what I figured for the 7 bolt question, just making sure I wasn't missing something.

On the tail shaft differences I believe it is just a matter of length and built in VSS or no built in VSS. My engine, harness and PCM are from a 2007 Silverado Classic (aka the 1999-2006 body style) so do you think I am fine with any 4L80e in that year range if we assume I am ignoring the above tail shaft info? I know pretty much any of them could be made to work, I just want it as simple as possible. Did the drive-by-wire change cause any differences???

The reason I am not concerned about the tail shaft is I am adapting it to a transfer case and I know I am going to have to change the output shaft. I DO want to find a 2wd version however because I am under the impression that ALL of the 2wds had the internal VSS, never a tail shaft version.

[Shon]

tailshaft bushing diameter is the difference.

[Critter]

Originally Posted by Shon

tailshaft bushing diameter is the difference.

Hmm...well I wonder if that could cause a problem with adaptation. Can anybody add any detail to that? Is it a year model thing or 2wd/4x4 issue? I am getting a lot of my info from Advanced Adapters (which we all know isn't 100% perfect) and they give the impression that they are all the same. Please elaborate if possible.

[Shon]

I called and talked to several tranmission shops b/c I was having issues with my yoke fitting the tailshaft, come to find out I bought an odd TH400 yoke that is not used hardly at all and it was not the right diameter but thru all of that I learned that there is a difference in the housing.

I also searched on 4l80 and found alot of info, it took time to figure it all out.

[Super73]

I run an early style behind my LS1.. I also run a F-body PCM and computer.

I wired the harness with an 80E connector (sounds like your is set the same). I then had to get a new harness for the 80E, but it was super simple do instal. Pull the pan off and hook it in. The guys at Scoggin Dickey new exactly what I needed. There is one other small thing that changes and I think it's the temp sensor. Again though, super easy to do.

[Critter]

Does anyone have any more details to add? I found some info saying the wiring connectors got updated in 93 and apparently stayed the same through 2006 (maybe longer). Just trying to gather as much info as I can and there isn't much around the web on the 80e.

[Captainfab]

I'm trying to find out some of this info as well. From what I have learned, the early 4L80E's didn't have the 'black box' (don't know the correct name for it)at the selector shaft and the later model ones do. I have a '92 model that does not have it, and the selector shaft isn't long enough to add one to it. I do know that the '96 models do have that box, so somewhere in between '92 and '96 is when that was added. As far as I know all the rest of the connections are interchangeable....at least thru 2000.

[Critter]

Good info! I found this also, looks like 93 is the magic year...

[Captainfab]

Good info, Thanks for posting that. Was there any other useful info where you found that?

[Critter]

Originally Posted by Captainfab

Was there any other useful info where you found that?

I don't remember exactly where I found it to be honest. The Performance Transmission Center website has alot of parts listed for the 80e and some of the parts list the year model applications. Sometimes thats helpful.

http://www.transmissioncenter.net/4L80E.htm

If you look just a little way down you will see what they are calling the neutral safety switch which is what I believe you referred to as the "black box".

I'm beginning to piece some of this together...

[Super73]

Go to performancetrucks.net and in their GM transmission section do a search for 4L80E. There is a ton of info there under the swap threads.. This is where I found most of my data 3 years ago.

[Super73]

here are a few threads I started there.. They might help.

http://performancetrucks.net/forums/...d.php?t=363878
http://performancetrucks.net/forums/...d.php?t=380148
http://performancetrucks.net/forums/...d.php?t=378433
http://performancetrucks.net/forums/...d.php?t=383229
http://performancetrucks.net/forums/...d.php?t=383909


And here is a search page for "80E Swap" from there.. You should be able to find a lot with this:
http://performancetrucks.net/forums/...archid=2736362

[Captainfab]

Thanks for the links Critter and Super73.....I'll check them out when I've got a little more time.

[y5mgisi]

In reading through this, am i correct in my understanding that the only thing needed to hook a 91 (what i have) 4L80E to a LS 4L80E harness is a new connector at the trans?

[storm9c1]

Originally Posted by y5mgisi

In reading through this, am i correct in my understanding that the only thing needed to hook a 91 (what i have) 4L80E to a LS 4L80E harness is a new connector at the trans?

It's mentioned elsewhere, but if you have a '91, you should also update all of the solenoids to be safe. My memory is fuzzy now, but there is a specific solenoid (someone else can chime in which one) that needs to be swapped out with a newer Holley solenoid for sure for use with a newer computer. I bet if you search the forum for "4L80E holley solenoid" it will come up. In fact this was discussed in another thread recently.

[y5mgisi]

THank you very much!

[clinebarger]

The Internal trans harness & the EPC solenoid will need to be updated with '94+ parts.

The '91-'93 harness isn't even serviced anymore because it was a terrible design.

[storm9c1]

The EPC solenoid -- yeah, that's the one that I was trying to recall that certainly needs upgraded. Cline is your man for transmission info here!

[y5mgisi]

Thanks storm and Cline!

Ok, so it looks like, i'll need this harness



http://www.bulkpart.com/2/product/4L...id/34446K.html

And im a little confused as to which solenoid i'll need. THere are two they are listing as the EPC.

1,



http://www.bulkpart.com/2/product/4L...id/34435B.html

And 2,



http://www.bulkpart.com/2/product/4L...id/34435C.html

Which of those will i need? And whats the difference?

[clinebarger]

This one (94-03) http://www.bulkpart.com/2/product/4L...id/34435A.html

[y5mgisi]

Interesting! Ok thanks! Do you happen to know what about it thats actually different? Or is it just that the late model ECM wont "actuate" that solenoid?

[engairuph]

Originally Posted by clinebarger

The Internal trans harness & the EPC solenoid will need to be updated with '94+ parts.

The '91-'93 harness isn't even serviced anymore because it was a terrible design.

What is the difference between the 2000 4l80e 4x4 and 2007 4l80e 4x4 trans? I don't see a rear sensor, no tone ring on output shaft? What all would have to be changed to change trans? Have a 2000 now and thought about changing

[storm9c1]

I think the VSS (speed sensor) was on the transfer case for a 4x4. Is that where yours is now? Or is it on the trans?