Turbo 400 / 4L80E

[bkahler]

Steve, if you had an Argosy that would work just fine. My Argosy has rear drum brakes with the parking brake located there. The 4L80E that I will eventually install in the Argosy came out of a box truck with the drum on the back of the transmission like the Classic's.

I haven't decided yet whether to sell the brake assembly from the 4L80E mainly because someday I would like to install a differential with disc brakes.

From what I have been told you would just need to swap out the tail housing and then come up with the parking brake parts.

Brad

[LimeyRich]

If that 4l80e is for sale for less than $400 and you know the owner, Snap it up!
Brad is absolutely right about the tailpieces they are completely interchangeable. Just pull the bolts, use a new gasket, and the tail housing and tail shaft you want.
Perhaps you and Brad should swap tailhousings?
Anyway the fly in the ointment might be finding a tailhousing with parking brake assembly that works for you.
Although it gave me fits and apoplexy during the "fitting" stage, I am now quite happy with the GMC/Chevy 3500 HD tailhousing, especially since I have rounded up the small parts.
Nothing new going on here, Transmission and all the parts I need are waiting in the freezing garage for me.
Nice neighbors, the house, pets, vets, and local wildlife have all been using up my time since the really cold weather hit. You all know the drill, when you have something really crucial to do, every would be Sargent has a hole to dig or fill somewhere.
All the best.Rich.

[Keyair]

Rich, it was not this one... but I found another for $200, and grabbed it yesterday!

Popped the pan off, and it looks great, but I plan a HD rebuild before use..
I think I will be asking you and Mel lots of questions when I get to fitting it!

[Keyair]

For anyone interested...
Car Craft Magazine June 2013 has a gem of an article in the "Junkyard Builder" series, on swapping in a 4L80E.

[92landyacht]

June 2013?

[Keyair]

Originally Posted by 92landyacht

June 2013?

Yes, I have a subscription, so I get mine early!
Give me time to give y'all a heads up!

[choctawmel]

Lot better to find a 4L80e for $200-400 and have it rebuilt than the 'Good' one I got that had to be pulled 2 more times to: 1) replace 'stock' torque convertor w/$9?? racing multi-clutch one. Only to turn around and 2) pull 'good' transmission and pay another $9?? to get it rebuilt. All in less than 400 miles (I think was)
The 'tail-shift and housing' I started with was 'heavy duty' which after searching in every junk yard the world over for the e-brake to match I found that 'HD' 'tail shaft/housing was only sold on the tilt-bed wreckers. Found that out from the wrecker drive at the last back woods junk yard I visited (was that banjo music I heard) who couldn't find one new/used for his wrecker. I exchanged the 'HD' for a medium duty off a junkyard 400 w/e-brake to match. It's good to find a 'old' RV grave yard.

[Keyair]

Thanks Mel.
I agree.
My research on rebuilding for this task is in the infant stages...
HD Frictions, Kevlar Bands, and 34 element sprag, for sure.
I am reading about adding straight cut planetaries like in the TH475 and I am led to believe that the 4L85E has S/C planetaries too.
Still digging!

[LimeyRich]

Hi Guys: Hope everyone is doing well. I am feeling pretty good at the moment, and I am finally able to make some progress with the transmission refresh.
Last week I lifted the 4L80 into a position in which I could start teardown and inspection, and every part I have checked so far looks brand new, with no obvious wear. Hopefully this will continue throughout the refresh.
So far this week I have completed the TransGo pressure relief mods on the
pump. I have the override clutch apart and the new clutches soaking in transmission fluid. Both the new and used "paper" clutches from the override are measuring out at exactly 3mm in thickness, no scratches,tears, dishes, rough spots to be found.Tomorrow I will be inspecting the override piston, and hopefully re-assembling the override and input shaft assembly. Then I will set the pump and override/input shaft assemblies to one side while I address the rest of the innards!

Choctawmel, did that tail housing look like my HD unit? mine is the 15,000lb gvw unit from the 3500HD box and chassis trucks (NAPA has all the brake parts for it). But, i believe that there may be a 20,000lb GVW unit out there as well. A little consistency from GM would have been nice.

I will add my latest pics later tonight or tomorrow.
Rich.

[LimeyRich]

These Pics are high def, and I used a tripod, so click and view the larger versions.


4l80e on transmission jack, showing brake hub without drum. 6yr old 120V Impact wrench, best $45.00 (I think $45) I ever spent.


for Choctawmel. 9" e-brake drum, shoes, actuating lever, and spring. Small springs not in pic.


transmission on 3/4' ply,on plastic bucket. Hanging from come-along, and strapped and wired to 4x6 post,and 2x4framing.


holding this beast at a good working height for me


This O-ring on input shaft must be removed first.


Input shaft, front seal, front plate of pump. Notice red dot,white dot, and black dot in bellhousing? Do not know if they are factory, but thanks to someone for the alignment marks! (As I take the trans apart I am noticing little notes in black magic marker, from the previous "GM Goodwrench" rebuild.)


Pan off.


Internal wiring harness, Typical GM attaching clips, plus some retaining clips.

OK that's my limit for uploads. Everything very straightforward so far.
BUT time for some provisos, and acknowledgements.
I would never try to do this without a copy of the ATSG 4l80e book, got mine on Amazon, and they are on e-bay.
Here on Airstream Forums we really have a wonderful group of supportive Airstreamers, and we do get into some strange and wonderful situations with our Airstreams!
1) I am not a transmission guy, and it's been ages since I was inside an auto trans. All of this work is difficult, slow, and a struggle for me. I might screw up! So be very cautious about copying what I am doing! I am very glad to share my experience, but ultimately you are on your own.
2) If it wasn't for the availability of parts, manuals, pics,and videos on the internet, and the kindness of the people at various supply companies, this would be a very expensive disaster.
3) Thanks to Jake, at Jakes transmissions for some early advice, next time I get out past La Grange I owe him a beer..Thanks to all the folks who have posted their 4L80e swaps and builds with pictures at various forums. Thanks to "Twisted Wrench" on "Help Wrench.com". Also,"Blown 3qtr" On PerformanceTrucks.net for a great at-home 4l80e rebuild pictorial. But especially Jake again, for the rebuild at "NastyZ28 Forums". I mention Jake twice because fixing transmissions is his livelyhood, but he is ready and willing to help someone else .The list goes on, but you get the picture, and I am preaching to the choir here.
All the best! Rich.

[choctawmel]

Last time I rebuilt an automatic was when I was in the Army at the 'craft shop' was a Dodge 737. I'm glad the shop I took it to charged only $903 to rebuilt it when everyone else was $2000 and up. But then I have done (and sent) some business there way over the years.
mel

[LimeyRich]

Mel, the last time I was inside a hydramatic it was from an old Pontiac , and I am pretty sure I was still in my teens, and I was helping my brother-in-law. He had been an F-101 Voodoo mechanic, so he could fix anything! (especially if it acted spooky)
I too was trained as an A&P mechanic, (I haven't retained much, but I am not afraid of getting into mechanical things!) lol.
Ok, tons of interruptions in the last two weeks, so progress is slow.
I also bought a few additional internal small parts I wasn't completely happy with.
*** One big change is that I found the ATSG 4L80e video,so i bought it too and I have watched it through twice already! $67.00 for the video and book is chicken feed, and wow, what a big change in familiarity with the transmission it brings. I heartily recommend buying the video book combo if a 4L80e rebuild is in anyone's future.***
I have plenty more pics to load, I just do not have time for a day or two.
All the best. Rich

[LimeyRich]

Here are some of my 4L80e teardown and reassembly pictures I promised (sorry I am slow, but that's just the way it is for me now).
A slight segue follows.
As I have said before, my 4L80e comes from a 1996 3500HD, which perhaps bears a little clarifying for anyone else contemplating this swap.
My 4l80e appears to be a 1996 model.
This 4l80e is a 1996 rebuild by GM Goodwrench. (That doesn't mean it is a 1996 transmission,or that it was re-manufactured in 1996.) Just that GM Goodwrench sold it as a replacement rebuild for the 4L80e originally in the 1996 3500HD chassis/cab box truck (by the way the chassis /cab units are the only 3500HD designated GM trucks for 1996,(15,000.00 lb GVW) all others are just GM/Chevy 3500 series (12,900.00 lbs GVW, ? ?).)
There appears to be an even heavier version sold as a bare wrecker chassis that could come with a 454 and 4L80e, instead of the more expensive Diesel, this seems a strange item to economise on. (but, I cannot prove this statement, nor do I care! )
True HD's are also rare as hen's teeth, so much so that "truck collectors" may be hoarding them, weird huh?
OK, back to the subject of getting a 4L80e into my 345.
Attachment 184044
fluid pump removed and sitting in the pan.
Attachment 184045
pump case and stator apart
Attachment 184046
Recess for front seal, showing enlarged drainhole per TransGo specs for preventing front seal blowout.
Attachment 184047
Front gasket, and overrun (Overdrive) clutch with inputshaft, removed from trans.
Attachment 184048
partially disassembled.
Attachment 184049
closeup of overdrive clutch
Attachment 184050
Seal and gasket pack from my rebuild kit
Attachment 184051
bands, clutch facings, steels, and bushing.
Attachment 184052
clutch facings soaking in Dextron VI
Attachment 184053
overrun clutch apart, showing steel and paper clutch facings.

OK, that's all I can upload in one session, I will add more soon. In the meantime I am waiting for some replacements for parts I am not happy with, ( The pump stator relief I drilled wrong, .015 oversize! OOPS, grabbed the wrong #drill bit, and one spring pack that I damaged when compressing it ) The super really yelled about that!
A criticism I had read about GM Goodwrench rebuilds appears to be true, it has been intimated on the internet that they are less than fully careful about Goodwrench rebuilds. Especially when reusing hard parts that are not actually faulty, or out of spec, but are not as good as original
condition plus normal minor wear.
In my transmission the rear planetary gears have damaged teeth, they rotate freely but are looser than the front planetarys. There are no matching wear or damage marks on the sun gear, sun shaft or main shaft though. With no other sign of metal or foriegn object damage present, this indicates to me that the original sun gear and rear planetarys were damaged by a substantial piece of metal debris going through them, with resulting irregular multiple gouges on tooth crowns to a depth of about .035". I'm guessing that on inspection the rear planetarys were apparently considered "good enough", and still within maximum runout tolerance, so back in they went. I doubt any testing procedure of the finished rebuild would show anything , perhaps a slightly noisier gear sound.
Now I cannot categorically swear that GM Goodwrench overlooked this, but I have no other explanation.
I cannot trust obvious visual damage, so the planetarys are being replaced. I was lucky enough to also find a good rear extension shaft with brake backing plate and yoke from a 3500HD. This shaft shows far less wear than my 4L80e's extension shaft, yeah!
In conclusion, so far the 4l80e rebuild is a mixed bag of pluses and mnuses, but fixing things wrong at this stage is a big plus.
All the best.Cheers! Rich.

[LimeyRich]

When I can figure out why my pictures don't load i will redo this. Bah humbug!!!! ( more or less) : angry::a ngry::an gry:

[92landyacht]

Try hosting the pictures on another site (imageshack.us or tinypic.com) and then simply attach the pic's link through the "insert image" comand button.

[LimeyRich]

Wife says it is because I am too slow at writing text, and the site times out.
Thanks for the hint 92landyacht. I will try again.
All the best. Rich

[LimeyRich]

Here are some of my 4L80e teardown and reassembly pictures I promised (sorry I am slow, but that's just the way it is for me now).
A slight segue follows.
As I have said before, my 4L80e comes from a 1996 3500HD, which perhaps bears a little clarifying for anyone else contemplating this swap.
My 4l80e appears to be a 1996 model.
This 4l80e is a 1996 rebuild by GM Goodwrench. (That doesn't mean it is a 1996 transmission,or that it was re-manufactured in 1996.) Just that GM Goodwrench sold it as a replacement rebuild for the 4L80e originally in the 1996 3500HD chassis/cab box truck (by the way the chassis /cab units are the only 3500HD designated GM trucks for 1996,(15,000.00 lb GVW) all others are just GM/Chevy 3500 series (12,900.00 lbs GVW, ? ?).)
There appears to be an even heavier version sold as a bare wrecker chassis that could come with a 454 and 4L80e, instead of the more expensive Diesel, this seems a strange item to economise on. (but, I cannot prove this statement, nor do I care! )
True HD's are also rare as hen's teeth, so much so that "truck collectors" may be hoarding them, weird huh?
OK back to the subject of getting a 4L80e into my 345.

fluid pump removed and sitting in the pan.

pump case and stator apart

Recess for front seal, showing enlarged drainhole per TransGo specs for preventing front seal blowout.

Front gasket, and overrun (Overdrive) clutch with inputshaft, removed from trans.

partially disassembled.

OK, that's all I can upload in one session, I will add more soon. In the meantime I am waiting for some replacements for parts I am not happy with, ( The pump stator relief I drilled wrong, .015 oversize! OOPS, grabbed the wrong #drill bit, and one spring pack that I damaged when compressing it ) The super really yelled about that!
A criticism I had read about GM Goodwrench rebuilds appears to be true, it has been intimated on the internet that they are less than fully careful about Goodwrench rebuilds. Especially when reusing hard parts that are not actually faulty, or out of spec, but are not as good as original condition plus normal minor wear.
In my transmission the rear planetary gears have damaged teeth, they rotate freely but are looser than the front planetarys. There are no matching wear or damage marks on the sun gear, sun shaft or main shaft though. With no other sign of metal or foriegn object damage present, this indicates to me that the original sun gear and rear planetarys were damaged by a substantial piece of metal debris going through them, with resulting irregular multiple gouges on tooth crowns to a depth of about .035". I'm guessing that on inspection the rear planetarys were apparently considered "good enough", and still within maximum runout tolerance, so back in they went. I doubt any testing procedure of the finished rebuild would show anything , perhaps a slightly noisier gear sound.
Now I cannot categorically swear that GM Goodwrench overlooked this, but I have no other explanation.
I cannot trust obvious visual damage, so the planetarys are being replaced. I was lucky enough to also find a good rear extension shaft with brake backing plate and yoke from a 3500HD. This shaft shows far less wear than my 4L80e's extension shaft, yeah!
In conclusion, so far the 4l80e rebuild is a mixed bag of pluses and minuses, but fixing things wrong at this stage is a big plus.
All the best.Cheers! Rich.

P.S. This is a re-post with just 5 pics. Original post with ten pics did not work

[LimeyRich]

Ok rest of the pics that go with my previous post.


Clutch drum , showing steels and paper facings, and the spring retainer that I crushed out of shape by using the wrong spring compressing technique. The retainer is the part with all the holes in it.


All the pieces apart


new seals and gaskets


new steels and paper clutch facings


some new paper clutch facings soaking in Dextron VI.

[LimeyRich]

disassembled input shaft with overrun clutch (overdrive), and spring retainer before I ruined it.


closeup of used clutch facing, no signs of wear at all.


valve body draining in pan


Hydraulic accumulator



The 4l80e repair book shows three spring chambers in use. The third chamber (torque signal), is not used except in very early models



Lower face of valve body.

More pictures coming in next post.

[LimeyRich]

Center support snapring in the wrong, but factory, position. All the transmission rebuilders caution about installing the snapring in this 9 o'clock position as there are no case webs anywhere near it. I can imagine the snapring bouncing and flexing as the transmission works, and ultimately breaking or coming loose.


Another shot that clearly shows the lack of support for the snapring. The snapring should be turned 90 degrees from this position.


No moving parts left in the case

On the workbench.
All the clutches (except overrun), the 2 bands, and the gearset with main shaft, and output shaft showing. Pump and new stator pre-assembled. My IBM Thinkpad, with the ATSG 4L80e service video playing.
The labelled tin cans to the left of the laptop contain all bolts and small parts according to sub-assembly.
Tools ,assembly lube, hand cleaner, paper towels, blue paper shop towels, and Coffee cup, just a few things to keep close.


An important shot of my paper towels (you will need tons of good rags or, paper towel. Even a drained transmission dribbles a lot of fluid. Slipping on a puddle of trans' fluid HURTS) along with supporting cast members. Clear view of the gearset.


In the far right corner the blue TransGo box for the Ist stage 4L80e mods, recommended for heavy duty use 4l80e survival (not racing mods).
The ubiquitous universal tool in the foreground. The tin can under the hydraulic pump is also an assembly tool.
concrete panel garage firewall in the background.

That's about it until my replacement parts show up in a couple of days.
Hope you enjoyed this so far.
All the best. Rich.