GMT 900 Trucks General Discussion 2007 - 2013 Trucks | General Discussion

6L80 to 4L80 Conversion

Thread Tools
 
Search this Thread
 
Old Jun 2, 2012 | 11:17 AM
  #1  
Three6GMC's Avatar
Thread Starter
TECH Addict
15 Year Member
Loved
Liked
iTrader: (11)
 
Joined: Mar 2010
Posts: 2,165
Likes: 27
From: Corpus Christi
Default 6L80 to 4L80 Conversion

Alright I know why would I want to go backwards. Well shooting for over 1000hp and right now engine is almost complete and with the best parts in it shouldn't have any trouble at all making my goal and then some. Now I have looked high and low and just doesn't seem like the 6l80 is gonna hold up to much abuse especially with me being a weekend warrior. I don't want to be constantly replacing the transsmission and have my truck down. So the only logical thing I have seen to do is to swap out to a 4l80. My plans if gonna go 4l80 is to get a Rossler Terminator trans and be done with it. Think this is a good way to go? Trans seem stout and with a 1800hp rating should be more then up to the task. Oh and has the ability to throw in a trans brake for those killer 4wd launches! Question: What will have to be done to get this trans to work right in the truck. I imagine just a factory harness and 4 speed tune specs right? Should be pretty much straight forward as the older nnbs trucks had the 4 speeds as well as the current 4.8s. I know I'm gonna have to change my gauge cluster and other little things but are the main parts going to be compatable? Will my computer control the 4 speed?

Last edited by Three6GMC; Jun 2, 2012 at 11:52 AM.
Reply
Old Jun 2, 2012 | 11:29 AM
  #2  
62nalide's Avatar
TECH Fanatic
iTrader: (1)
 
Joined: Sep 2010
Posts: 1,953
Likes: 2
From: Dallas TX
Default

Im in the same boat i will also like to know
Reply
Old Jun 2, 2012 | 04:14 PM
  #3  
iamkeniff's Avatar
Moderator
iTrader: (16)
 
Joined: Apr 2007
Posts: 5,365
Likes: 3
From: Gonzales, la
Default

just take the harness and tcm from a 07-08. do the wiring mods, segment swap. bam the truck will never know except if you try to pull it into 1st being that your shifter is setup to only go down 1 notch.
you MAY have to take the truck up to the dealer with a 5.3/60e vin so they can flash that into the ecm so it will read the 4 spd but im not certain on that.


this is all in theory though.
Reply
Old Jun 2, 2012 | 04:39 PM
  #4  
1slow01Z71's Avatar
Tin Foil Hat Wearin' Fool
iTrader: (36)
 
Joined: Oct 2004
Posts: 23,204
Likes: 4
From: Austin, TX
Default

If you've got a place down there I could bring my truck on a trailer and do the swap over a weekend. We could swap harnesses, sensors, ecm/tcm, transmissions and clusters so everything works like factory. If you're interested shoot me a PM.

BTW I finally got me a complete 6.2 exhaust
Reply
Old Jun 2, 2012 | 04:59 PM
  #5  
Three6GMC's Avatar
Thread Starter
TECH Addict
15 Year Member
Loved
Liked
iTrader: (11)
 
Joined: Mar 2010
Posts: 2,165
Likes: 27
From: Corpus Christi
Default

I'll let you know that might be the easiest way to do a complete swap. And bout time on that exhaust lol I actually have a buddy who is gonna take his whole system off this next weekend. He already gave it to me so gonna polish the tip up and hold it as a spare. I'm actually starting to have a nice collection lol 3 and counting. 2 just muffler back to tip and one complete!
Reply
Old Jun 2, 2012 | 05:04 PM
  #6  
Three6GMC's Avatar
Thread Starter
TECH Addict
15 Year Member
Loved
Liked
iTrader: (11)
 
Joined: Mar 2010
Posts: 2,165
Likes: 27
From: Corpus Christi
Default

Hey niff any idea what transfer case I would have to go with?
Reply
Old Jun 2, 2012 | 05:13 PM
  #7  
Foxxer's Avatar
TECH Apprentice
 
Joined: Feb 2010
Posts: 374
Likes: 0
From: Dubai, U.A.E.
Default

Originally Posted by Three6GMC
Hey niff any idea what transfer case I would have to go with?
Never saw a guy going that way do driveshafts measure the same?
Reply
Old Jun 2, 2012 | 05:16 PM
  #8  
Three6GMC's Avatar
Thread Starter
TECH Addict
15 Year Member
Loved
Liked
iTrader: (11)
 
Joined: Mar 2010
Posts: 2,165
Likes: 27
From: Corpus Christi
Default

Lol yeah well wouldn't be but power permits something stronger then my 6l80. I really don't know if it would measure the same I think my driveshaft is gonna be shorter as the 4l80 is a longer trans then the stubby 6l80
Reply
Old Jun 2, 2012 | 06:04 PM
  #9  
1slow01Z71's Avatar
Tin Foil Hat Wearin' Fool
iTrader: (36)
 
Joined: Oct 2004
Posts: 23,204
Likes: 4
From: Austin, TX
Default

Your tcase should work with the 80e just fine but you will the need the tcase to trans adapter housing. Let me know if you decide. I think it will be the cheapest way for both of us to get what we want. I'm not going nutts like your crazy ***

I just want a turbo L76
Reply
Old Jun 2, 2012 | 07:54 PM
  #10  
gonzo 6.2's Avatar
TECH Veteran
iTrader: (8)
 
Joined: Oct 2002
Posts: 4,516
Likes: 15
From: oregon
Default

why not do a 6L90E ????
Reply



All times are GMT -5. The time now is 04:03 PM.