4L80E in an 86? - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans Advertise
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Transmission - Rearend
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 05-17-2019, 04:13 AM
Registered User
 
Join Date: Dec 2018
Location: Bunker Hill, West Virginia
Posts: 21
Wiki Edits: 0

Thanks: 12
Thanked 0 Times in 0 Posts
4L80E in an 86?

So I bought this van for the engine and trans thought it was a 700R4 but after getting it on the ground found out it is a 4L80E a six speed auto. Question is what will it take to put it in a 1986 pickup.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 05-17-2019, 07:09 AM
55 Tony's Avatar
Registered User
 
Join Date: Nov 2018
Location: Cocke County, TN
Posts: 646
Wiki Edits: 0

Thanks: 100
Thanked 105 Times in 91 Posts
That's a 4 speed. I believe it will need some type of aftermarket computer. I'd like to build one for my car someday. They are, or can easily be as strong as a th400. They use some of the same parts.
__________________
Young enough to learn ... too old to remember.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 05-17-2019, 07:11 AM
Old(s) Fart
 
Last wiki edit: Wheelbase database Last photo:
Join Date: Jan 2007
Location: Virginia
Posts: 5,273
Wiki Edits: 1

Thanks: 89
Thanked 575 Times in 511 Posts
The 4L80E is a four speed trans (hence the "4" in the name). I ASSUME your "86 pickup" is a C/K full size. These came with the 4L80E in the last year of production for that body style (1991), so it obviously can be done. The 2WD conversion is pretty easy, just requires a custom driveshaft and crossmember relocation. The 4WD conversion is more problematic since you need the one-year-only transfer case adapter. The newer t-case has the drop to the front axle on the wrong side.
Reply With Quote Quick reply to this message
 
  #4 (permalink)  
Old 05-17-2019, 10:27 AM
Registered User
 
Last photo:
Join Date: Jan 2012
Location: Grand Rapids, MI
Posts: 1,723
Wiki Edits: 0

Thanks: 212
Thanked 360 Times in 289 Posts
What transmission do you have in the squarebody now?

What engine are we talking about?
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 05-17-2019, 12:38 PM
Registered User
 
Last photo:
Join Date: Apr 2007
Posts: 11,846
Wiki Edits: 0

Thanks: 126
Thanked 962 Times in 764 Posts
Quote:
Originally Posted by 86squarebody View Post
So I bought this van for the engine and trans thought it was a 700R4 but after getting it on the ground found out it is a 4L80E a six speed auto. Question is what will it take to put it in a 1986 pickup.
4L80E is the electronic controlled heavy duty 4 speed automatic outgrowth from the 3 speed TH400. Unlike the 3 speed TH350 that morphed into the mech/hyd 700R4/4L60 then to the electronic 4L60E, there is no intermediate mech/hyd design for the TH400 to 4L80E.

So if you want to run it you need a controller, but since the van has this transmission it also had electronic fuel injection which also needs a computer.

The next step in assisting you is knowing what direction you want to go in and what was the year and model of the van as the EFI and the control systems for the various EFI's can vary from year to year as well as by model with in these years. TBI was common from 1987 through 95. The L30 and L31 SBC come in 96 going to 2002 in some models. Most of these have multipoint central injection, but some 96 and 97 vans retained TBI. The 4L80E from the beginning in 1987 would have a controller in the original vehicle. It was not until 92 with the introduction of the 4L60E that all vehicles would have a transmission controller in the computer.

The 4L80E can be run manually without a controller but there is no modulation of line pressure, it is maxed all the time which results in sudden and hard slamming shifts.

So we need some of your thoughts on how you want to proceed. Stand alone controllers are about a grand buck if you want a data point, simplest answer if your staying with factory EFI is to have the original computer and wire harnesses.

Bogie
Reply With Quote Quick reply to this message
The Following User Says Thank You to BogiesAnnex1 For This Useful Post:
86squarebody (05-17-2019)
  #6 (permalink)  
Old 05-17-2019, 04:00 PM
ericnova72's Avatar
More for Less Racer
 
Join Date: Jan 2007
Location: S.W. Lower Michigan
Age: 52
Posts: 16,945
Wiki Edits: 0

Thanks: 245
Thanked 2,944 Times in 2,481 Posts
Quote:
Originally Posted by 55 Tony View Post
That's a 4 speed. I believe it will need some type of aftermarket computer. I'd like to build one for my car someday. They are, or can easily be as strong as a th400. They use some of the same parts.
They can be set up "brain dead" as a full manual valvebody, driver makes all up and downshifts manually, if you want to avoid the cost of a stand alone controller.

Any hotrodder or racer should have no problem enjoying that! Even easier than a stick shift manual trans, you don't have to leg stroke a clutch pedal and lift/apply the gas pedal at every shift....just mash the gas and bump the shifter handle to the next gear
Reply With Quote Quick reply to this message
The Following User Says Thank You to ericnova72 For This Useful Post:
86squarebody (05-17-2019)
  #7 (permalink)  
Old 05-17-2019, 04:09 PM
Registered User
 
Join Date: Dec 2018
Location: Bunker Hill, West Virginia
Posts: 21
Wiki Edits: 0

Thanks: 12
Thanked 0 Times in 0 Posts
Well pulling the engine and tranny was pretty brutal. I had no intention of staying with TBI that is in it was going carburator and would still like too. I havent looked real hard yet because of the rain but I am pretty sure there are two computers. The ECU is under the drivers seat then there is another under the body passenger side behind the tranny. If I have to get a driveshaft and move the crossmember plus all the other it is not worth it. If I can put the 4L80E and it's computer in with maybe a few tricks to get it to shift right, I don't mind hard that is doable. If I hae to buy a controller and go through a bunch of other coversion I would rather sell it and get a 700R4. I hate to let it go it worked flawless and the fluid is red no sign of burn. I know about the line pressure on these had a Formula with a 4L60 E and a little button when pushed would slam you.
I can splice harnesses back together or make new ones if I have too.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 05-17-2019, 04:22 PM
Registered User
 
Join Date: Dec 2018
Location: Bunker Hill, West Virginia
Posts: 21
Wiki Edits: 0

Thanks: 12
Thanked 0 Times in 0 Posts
It has a TH400 in it now with a 305 probably going to a 350 but it will stay a small block
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 05-17-2019, 04:48 PM
Registered User
 
Last photo:
Join Date: Jan 2012
Location: Grand Rapids, MI
Posts: 1,723
Wiki Edits: 0

Thanks: 212
Thanked 360 Times in 289 Posts
Run the 400.

I have had over a dozen squarebodies most of them runnong 4.56 gearing..
You dont need overdrive with a squarebody.
Your pushing do much wind at 80mph being up in the powerband is a good thing.
Current 87 has a 700 and the overdrive is absoultly unnecessary.

You can bolt a number of transfer cases behind the 400
Dont need to mess with linkage.
Have higher power limits per dollar.
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 05-17-2019, 05:17 PM
ericnova72's Avatar
More for Less Racer
 
Join Date: Jan 2007
Location: S.W. Lower Michigan
Age: 52
Posts: 16,945
Wiki Edits: 0

Thanks: 245
Thanked 2,944 Times in 2,481 Posts
Quote:
Originally Posted by 86squarebody View Post
It has a TH400 in it now with a 305 probably going to a 350 but it will stay a small block
700R4 is a big step backwards in strength from a TH-400 you have now....or the 4L80E conversion. If you intend to make 400HP or better, the 700R4 in stock form is a bad idea, if you intend to ever make 500+ HP then even a heavily modified 700R4.4L60/4L65 isn't the greatest choice, durability will always be suspect.

On the mechanical side, sliding the trans crossmember back and drilling new mount holes is easy. You have a TH-400 driveshaft which has the same splined yoke on it the 4L80e has to have, so just have your current driveshaft shortened by a local driveshaft/heavy truck repair shop.
Or anyone with a lathe and a welder can shorten it, if you know any old school machinists near you. Or you may be able to have the Van parts shortened and re-use those.
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 05-17-2019, 09:05 PM
Registered User
 
Join Date: Dec 2018
Location: Bunker Hill, West Virginia
Posts: 21
Wiki Edits: 0

Thanks: 12
Thanked 0 Times in 0 Posts
4L80E in an 86

Okay so I have a nice 4L80E with torque converter and computer to get rid of. It is too much to go through right now, crossmember mod and driveshaft shortening it is just not worth it the TH400 is a Jasper rebuild with a pretty agressive shift kit. All I am trying to do right now is get it dependable because it needs bodywork. Not bad now but if I don't get back to it soon it will be. Just going to do the 350 to run strong and reliable and get it in. Thanks for all of the input I was having a hard time with this but the TH400 is proven.
Reply With Quote Quick reply to this message
  #12 (permalink)  
Old 05-18-2019, 04:28 AM
75gmck25's Avatar
Registered User
 

Last journal entry: Engine replacement
Last photo:
Join Date: Aug 2006
Location: Alexandria, VA
Posts: 2,387
Wiki Edits: 0

Thanks: 4
Thanked 192 Times in 177 Posts
Most squarebody folks I know would love to have a 4L80E in their trucks, since its as strong as a TH400 and also has overdrive. You do need a controller to replace the computer, but there are multiple sources for what you need. However, if you are running 3.73 or higher gears, or 35" tires, you probably don't really need overdrive that much.

2WD Squarebodies are relatively forgiving for engine and transmission swaps since you have a lot of space to work with. I've been told the frame is already drilled for multiple crossmember locations, but I've never verified. I don't think this swap would be that difficult.

Bruce
Reply With Quote Quick reply to this message
  #13 (permalink)  
Old 05-18-2019, 05:04 AM
55 Tony's Avatar
Registered User
 
Join Date: Nov 2018
Location: Cocke County, TN
Posts: 646
Wiki Edits: 0

Thanks: 100
Thanked 105 Times in 91 Posts
Can you put it in the back of my daughters Mamma Van on her way down here thursday? Someone correct me if I'm wrong, but the computer isn't worth anything unless it's going back into a vehicle with a computer. It would need a complete rebuild and a shift kit.
__________________
Young enough to learn ... too old to remember.
Reply With Quote Quick reply to this message
  #14 (permalink)  
Old 05-18-2019, 05:25 AM
S10xGN's Avatar
Gotta love a turbo!
 

Last journal entry: Body on Frame today.
Last photo:
Join Date: Aug 2004
Location: Port Neches, TX
Age: 65
Posts: 2,490
Wiki Edits: 0

Thanks: 0
Thanked 224 Times in 208 Posts
GM did make a diesel truck version of the '80E that was non computer-controlled. Not sure what's involved to get this, prolly a valve body swap at least...

Russ
Reply With Quote Quick reply to this message
  #15 (permalink)  
Old 05-18-2019, 05:47 AM
Registered User
 
Join Date: Dec 2018
Location: Bunker Hill, West Virginia
Posts: 21
Wiki Edits: 0

Thanks: 12
Thanked 0 Times in 0 Posts
Thanks for the info. there are multiple holes for the cross member already in the frame have seen on you tube that it is not that big a deal maybe a little welding at most but then it comes to shortening the driveshaft. Mine has a two piece. It was actually what they called a heavy duty half ton it has 3/4 suspension rides like a rock looks like its four wheel drive so I don't have a problem with hard shifts or any of that. I also saw some switches used to get it into first. I do not see an advantage really gas mileage isn't that bad about 15-17mpg and it isn't driven a lot it is just something I play with my toy. Like I said I need to focus on the body before I don't have one.
Reply With Quote Quick reply to this message

Recent Transmission - Rearend posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Insurance
Please select your insurance company (Optional)

Log-in



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
4L80E behind 4.3 V6? Torque454 Transmission - Rearend 20 08-08-2013 06:32 PM
4L80E Into 79 C-10 Pickup Torque454 Transmission - Rearend 3 06-25-2010 08:28 AM
Difference between pre '86 and post '86 350? flyinv55 Engine 6 10-21-2007 01:41 AM
Need some tranny help. 4l80e Bruce Wang Transmission - Rearend 3 09-19-2005 03:19 PM
First 4L80E build questions. bugsdad Transmission - Rearend 12 10-22-2004 07:40 PM


All times are GMT -6. The time now is 06:22 AM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.