6L80/90e's How they work

[MN C5]

Anyone have links to cut aways or articles relating to how they function.

[carneb]

Cutaway view and tech info on operation (not comprehensive)

http://www.cadillacfaq.com/stsfaq/tsb/data/tsb/05-07-30-023.pdf


Exploded parts view and parts listing

www.transtarindustries.com/catDownload.asp?ID=708

They are the best I've found but would love to find more info on the programming side.

[gmh308]

Black art! :shock:

Seriously, that Transtar and Cadi info is the best I have found & seen so far too.

These trans's are very simple. Mostly a set of solenoid controlled clutches (and one sprag/roller). 5 clutch control solenoids. One shift pressure solenoid. 2 actuator solenoids (TCC). A few pressure switches, a temperature sensor, selector position switches and input & output speed sensors. The complexity is in the controller and the way it works hand in hand with the engine control module to create smooth and timely shifts for all (most) situations.

HPT has just improved their depth with the A6's from shallow to very deep with a new and very needed release. Am sure the EFILive guys are working this very minute to go further into this trans controller and even deeper than their already class leading capability.

Now the aftermarket & tuners have a whole new field of data to play with so the knowledge level should go way up. :grin:

[MN C5]

I'd like to flash a C6 OS in the the TCM..and see what that does...

[GMPX]

HPT has just improved their depth with the A6's from shallow to very deep with a new and very needed release. Am sure the EFILive guys are working this very minute to go further into this trans controller and even deeper than their already class leading capability.

While the self proclaimed tuning leaders play catchup with the A6 tuning capabilities many EFILive shops have been creating some awesome A6 tunes for months. I don't doubt there is many, maybe even thousands more tables and calibrations left inside the A6 TCM, but will they make the A6 shift like a Powerglide with a shift kit...doubt it.

Cheers,
Ross

[gmh308]

While the self proclaimed tuning leaders play catchup with the A6 tuning capabilities many EFILive shops have been creating some awesome A6 tunes for months. I don't doubt there is many, maybe even thousands more tables and calibrations left inside the A6 TCM, but will they make the A6 shift like a Powerglide with a shift kit...doubt it.

Cheers,
Ross

Agreed 100%. :)

[vetteboy2k]

While the self proclaimed tuning leaders play catchup with the A6 tuning capabilities many EFILive shops have been creating some awesome A6 tunes for months. I don't doubt there is many, maybe even thousands more tables and calibrations left inside the A6 TCM, but will they make the A6 shift like a Powerglide with a shift kit...doubt it.

Cheers,
Ross
Any chance that there will be more controls for the torque converter Pulse Width Modulation for lockup?

[joecar]

The only comphrensive documents explaining how the 6L80/6T75 transmissions function are these documents from www.helminc.com: (http://www.helminc.com:)

- 6 Speed RWD Transmission Technician's Guide (HM6SPEEDRWDTG)
- 6 Speed FWD Transmission Technician's Guide (HM6SPEEDFWDTG)

There doesn't seem the be a .pdf version available yet (neither are on the $100 CD)

[The Alchemist]

while I've got you here GMPX how do you reduce the horrible torque spark retard function on each gear change with the A6? Is it in the PCm or TCM? pulls almost 20 deg.
Cheers,
Mike

[vetteboy2k]

while I've got you here GMPX how do you reduce the horrible torque spark retard function on each gear change with the A6? Is it in the PCm or TCM? pulls almost 20 deg.
Cheers,
Mike
TCM has those controls

[The Alchemist]

under what heading mate?

[XLR8NSS]

I got rid of all that spark retard on the upshift by turning off torque management. It's in the TCM and they make it very easy to turn off. :D

[MN C5]

The only comphrensive documents explaining how the 6L80/6T75 transmissions function are these documents from www.helminc.com: (http://www.helminc.com:)

- 6 Speed RWD Transmission Technician's Guide (HM6SPEEDRWDTG)
- 6 Speed FWD Transmission Technician's Guide (HM6SPEEDFWDTG)

There doesn't seem the be a .pdf version available yet (neither are on the $100 CD)

Thanks JoeCar...Any idea how to get the Tech's Guide? I tried a couple of times and it appeared I needed a dealer code or it wasn't available..

Any transmission experts that could comment on the best hi perf pressure curves for the 3 modes in the TCM? How should they differ for each shift, ect... And the same thing with shift times I would assume that each shift should have slightly different characteristics depending on whats happening inside the tranny

[joecar]

Click on the CLICK HERE>> link under Vehicle Owner, Do It Yourself, Professionals in the upper left;

then select GM Powertrain in the dropdown and click Submit;

then look for HM-6-Speed-RWD-TG in the next dropdown and click Search;

that gets you to here: http://www.helminc.com/helm/Result.asp?Style=&Mfg=GMC&Make=HYD&Model=HM6S&Year=&Category=&Keyword=&Module=&selected%5Fmedia=&mscsid=RVUAMPNP4QQQ9PT8GFLPKG2QEFQP640C

[MN C5]

Beautiful instructions for a guy with internet ADD like me. lol Hopefully they will get the documentation up soon.


Click on the CLICK HERE>> link under Vehicle Owner, Do It Yourself, Professionals in the upper left;

then select GM Powertrain in the dropdown and click Submit;

then look for HM-6-Speed-RWD-TG in the next dropdown and click Search;

that gets you to here: http://www.helminc.com/helm/Result.asp?Style=&Mfg=GMC&Make=HYD&Model=HM6S&Year=&Category=&Keyword=&Module=&selected%5Fmedia=&mscsid=RVUAMPNP4QQQ9PT8GFLPKG2QEFQP640C

[joecar]

Oh, I didn't pay attention enough to see that they are doing inventory... they should be back up in a few days.

[gmh308]

The only comphrensive documents explaining how the 6L80/6T75 transmissions function are these documents from www.helminc.com: (http://www.helminc.com:)

- 6 Speed RWD Transmission Technician's Guide (HM6SPEEDRWDTG)
- 6 Speed FWD Transmission Technician's Guide (HM6SPEEDFWDTG)

There doesn't seem the be a .pdf version available yet (neither are on the $100 CD)

Hi JoeCar, how deep do these docs go? Are they brief overviews, or do they go into the "science" that runs these trans?

Congrats on the promotion!! :)

[joecar]

These tech guides contain the "theory of operation" specifically for the 6L80 and 6T75.

They show in very great detail (using very good artwork) how all the internal hard-parts and clutches fit together and interact as the PCM shifts from gear to gear... they show how each component performs it's function, and how each component is electronically/hydraulically applied and released.

They show all the hydraulic passages, all the checkballs, all the solenoids and the valvetrains they control, all the other valves, the pump, the torque converter...

they are not repair manuals, they do not contain any repair information (other than some mild diagnostic information such as "if checkball X is missing then the xyz clutch will not apply")...

if you want to know extensively how these transmissions function, then these are the books
(if only the actual hard parts were painted the same colour... ;)...)

See the 4 speed RWD section of the forum for some examples from the 4L60E/4L80E tech guides.

Oh, I didn't get promoted... :D ...I demoted myself from "In Charge of Lost Bolts" (plural) to "Lost Bolt Moderator" (singular)... :D

Cheers,
Joe
:cheers:

[gmh308]

Thanks Joe,

Looks like an interesting book. Many pages?

So now you are dealing with bolts on a one by one basis right? :) Much simpler but the salary is lower! :shock:

Cheers.


These tech guides contain the "theory of operation" specifically for the 6L80 and 6T75.

They show in very great detail (using very good artwork) how all the internal hard-parts and clutches fit together and interact as the PCM shifts from gear to gear... they show how each component performs it's function, and how each component is electronically/hydraulically applied and released.

They show all the hydraulic passages, all the checkballs, all the solenoids and the valvetrains they control, all the other valves, the pump, the torque converter...

they are not repair manuals, they do not contain any repair information (other than some mild diagnostic information such as "if checkball X is missing then the xyz clutch will not apply")...

if you want to know extensively how these transmissions function, then these are the books
(if only the actual hard parts were painted the same colour... ;)...)

See the 4 speed RWD section of the forum for some examples from the 4L60E/4L80E tech guides.

Oh, I didn't get promoted... :D ...I demoted myself from "In Charge of Lost Bolts" (plural) to "Lost Bolt Moderator" (singular)... :D

Cheers,
Joe
:cheers:

[joecar]

lol... :D

bolts can be managed collectively in a single group, collectively in multiple groups (which are mutually exclusive), or singly (a special case of "collectively in multiple groups")... but lost bolts are lost (their state is "not present") so there is no thing (collective or single) to manage... :D

[gmh308]

lol... :D

bolts can be managed collectively in a single group, collectively in multiple groups (which are mutually exclusive), or singly (a special case of "collectively in multiple groups")... but lost bolts are lost (their state is "not present") so there is no thing (collective or single) to manage... :D

LOL too! mmmmm.....into some quantum mechanics concepts....

So on that basis, when you find one, you actually find one or more even though they may be almost infinitely seperated, and when you put one you found in the right hole and turn it, both or all of them insert themselves into holes and turn in a plural sense. Except for those that exist in the anti-world, which undo as the real world bolts are done up.

Overall then, one might deduce and prove then that your job in indisputable fact did get easier? Even though you only thought it did! :) Given that the simple act of observing the bolts, causes them to change into nuts, which are out of scope of "lost bolts". :secret:

Cheers!

[joecar]

Yeah... I did physics at uni... ;) ...it was a good course... :cheers:

[joecar]

6L80 TG = 128pp
6T75 TG = 154pp

[gmh308]

6L80 TG = 128pp
6T75 TG = 154pp

Thanks Joe. So with 6L80/90 rear wheel drive, HM6SPEEDRWDTG is the right book? Only $35 for the book, and $144 for the shipping to downunder! :shock:
Nothing on Amazon either. :doh2:

[joecar]

$144 can't be right... give me a few days, I'll make some inquiries.

[duramaximizer]

Any books like that for the (cough* cough*) Allison for us guys that like torque.

[joecar]

Any books like that for the (cough* cough*) Allison for us guys that like torque.Try http://www.allisontransmission.com/publications/

I don't know the Allison transmission model numbers, and I don't know their publications/prices.

[duramaximizer]

The allison 1000 in the duramax trucks.

[Ratchthed]

We have been using Helm Manuals for years. It is the definitive source for Theory of Operation. Beware, it is Engineering level reading. Those books are not for the faint of heart nor those with ADD!

g

[joecar]

Yes, engineering/adavanced level... pre-requisite is understanding of general auto trans concepts/assembly.

[XLR8NSS]

I ordered a copy of the transmission(6L90E) manual and a set of service manuals for my truck('07 GMC 2500HD) from the link above. They should be here on Monday, can't wait to take a look. :)

[gmh308]

We have been using Helm Manuals for years. It is the definitive source for Theory of Operation. Beware, it is Engineering level reading. Those books are not for the faint of heart nor those with ADD!

g

Great to hear. I have the opposite of ADD (whatever that is) when it comes to interesting stuff like that. :grin:


Yes, engineering/adavanced level... pre-requisite is understanding of general auto trans concepts/assembly.

Any lack of detail would be a disappointment. And as the 6L80/90 run on black art, then a little quantum physics wont hurt either. :) Of course I dont think that being in two gears at the same time would be a simple curiosity like duality :doh2:.

Areas like having to factor in the inertia of the powertrain and whole vehicle is an interesting new element to mobility using clutch to clutch trans's. :shock:

One of my other curiosities at present is how crank angle error is determined and what total error it can deal with. No one at GM can seem to come up with a response. Maybe I will post a view of how it is determined and see what the debate uncovers.

In my search though, I did gain a very good insight into virtual fuel sensing for E85 etc fuels and how it works. :)

Have a good weekend all! :grin:

[joecar]

To say that this stuff is "interesting" is an understatement...!!! :D

[gmh308]

To say that this stuff is "interesting" is an understatement...!!! :D

Yes I tend to understate. I did grow up in Oz remember. :shock: You know we are prone to conservatism. :grin:

Of course if I grew up elsewhere, I might say that is "totally mind blowingly f__king fantastically informative" :grin: But that wouldn't be me. :shock:

[MN C5]

I ordered a copy of the transmission(6L90E) manual and a set of service manuals for my truck('07 GMC 2500HD) from the link above. They should be here on Monday, can't wait to take a look. :)

I'll split the cost with you if you send it my way when you've read it.:grin: BTW is the blower on your truck yet or are you waiting for next year:cucumber:

[duramaximizer]

I'll split the cost with you if you send it my way when you've read it. BTW is the blower on your truck yet or are you waiting for next year:cucumber:

Divide by 3 if you want to send to to me when your done with it. :)


Great to hear. I have the opposite of ADD (whatever that is) when it comes to interesting stuff like that.



Any lack of detail would be a disappointment. And as the 6L80/90 run on black art, then a little quantum physics wont hurt either. :) Of course I dont think that being in two gears at the same time would be a simple curiosity like duality .

Areas like having to factor in the inertia of the powertrain and whole vehicle is an interesting new element to mobility using clutch to clutch trans's.

One of my other curiosities at present is how crank angle error is determined and what total error it can deal with. No one at GM can seem to come up with a response. Maybe I will post a view of how it is determined and see what the debate uncovers.

In my search though, I did gain a very good insight into virtual fuel sensing for E85 etc fuels and how it works. :)

Have a good weekend all! :grin:

I have the same Anti ADD when it comes to interesting stuff and things that matter. :angel_innocent:

I had a guy explain to me how the E85 works. It is very simple and very complex all in the same sentence. Very cool and interesting.

Do they have these helms manuals for the Ally?

[gmh308]

I had a guy explain to me how the E85 works. It is very simple and very complex all in the same sentence. Very cool and interesting.



Amazingly simple. So simple they could have done it in the first place. Just took some creative types to get together and basically replace a $600 sensor with something that is "free", apart from the R&D cost. (not to oversimplify the VFS, it uses some complex tech, as you say, in a new and additional way.)

[ntae]

gmh308 when do you think we will see it in our holden's






Amazingly simple. So simple they could have done it in the first place. Just took some creative types to get together and basically replace a $600 sensor with something that is "free", apart from the R&D cost. (not to oversimplify the VFS, it uses some complex tech, as you say, in a new and additional way.)

[gmh308]

gmh308 when do you think we will see it in our holden's

My guess is sometime in the next 12 months at the outside. They could do it now, and no doubt have test cars on the road, but it is either program funding/engineering resources, or marketing does not feel the time is right, that may be delaying earlier introduction. Maybe now that the delayed Sportwagon is launched, other programs like E85 will get more focus.

[XLR8NSS]

I'll split the cost with you if you send it my way when you've read it.:grin: BTW is the blower on your truck yet or are you waiting for next year:cucumber:

Sounds like it's complicated, might take me a while to get through it. lol

Blower was ALMOST on this weekend but, was missing an important part and need my truck on Monday so I slapped the stock intake back on. I think on Tuesday it'll get done now. :)

[carneb]

I ordered a copy of the transmission(6L90E) manual and a set of service manuals for my truck('07 GMC 2500HD) from the link above. They should be here on Monday, can't wait to take a look. :)

Did you recieve your trans manual? How much detail does it contain on the actual operation of the gearbox? Or is it more about dissasembly/repair?

[joecar]

The 6L80 Hydra-Matic Technician Guide covers the complete theory-of-operation.

The ATSG 6L80 "TechTran" manual covers the complete disassembly/overhaul/repair with some theory (but not as much as the HMTG).

[carneb]

$120 for shipping and $25 for handling for a $35 book! :shock:

gmh308 did you end up finding one cheaper?

[gmh308]

$120 for shipping and $25 for handling for a $35 book! :shock:

gmh308 did you end up finding one cheaper?

Only via a mate over there. Have been too busy to organise so far. :doh2:

[XLR8NSS]

Did you recieve your trans manual? How much detail does it contain on the actual operation of the gearbox? Or is it more about dissasembly/repair?

Yep, I got it a while back. It shows the complete hydraulic circuits for each gear and much more. I have to go now but, will post back later.

[PSWired]

Can anyone with one of these manuals answer the following question for me:

What are the ramifications of spinning the torque converter of a 6L80e at idle speeds with no electrical power applied to the transmission? Range selector in P. Will damage be done after extended periods of doing this?

[gmh308]

Can anyone with one of these manuals answer the following question for me:

What are the ramifications of spinning the torque converter of a 6L80e at idle speeds with no electrical power applied to the transmission? Range selector in P. Will damage be done after extended periods of doing this?

Unclear how much damage if any will occur, but certainly the trans with no power on it does produce an unusual noise.

If the GM ECM fault action is to go into immediate engine off mode if TCM comms lost, probably a good chance it is not a good thing ("Immediate Landing"?). If it will continue to drive in limp mode in 3rd gear, then cant be too bad if not extended period ("Soft Landing"?)

The GM service manual does go into a discussion on the various fault modes, but dont have one at hand at present.

You could try www.repairprocedures.com for the manual info.

:cheers:

[PSWired]

Unclear how much damage if any will occur, but certainly the trans with no power on it does produce an unusual noise.

If the GM ECM fault action is to go into immediate engine off mode if TCM comms lost, probably a good chance it is not a good thing ("Immediate Landing"?). If it will continue to drive in limp mode in 3rd gear, then cant be too bad if not extended period ("Soft Landing"?)

The GM service manual does go into a discussion on the various fault modes, but dont have one at hand at present.

You could try www.repairprocedures.com for the manual info.

:cheers:

Thanks. I did notice the weird noise. I have the service manual and the fault action for power loss on the transmission IGN circuit (which is what I'm concerned with) is max line pressure among other things. Not engine shutoff.

I'm asking because the Transmission ignition circuit is not powered up during remote start in my application, and I need to know if I'll damage the trans if I leave it this way.

[gmh308]

Thanks. I did notice the weird noise. I have the service manual and the fault action for power loss on the transmission IGN circuit (which is what I'm concerned with) is max line pressure among other things. Not engine shutoff.

I'm asking because the Transmission ignition circuit is not powered up during remote start in my application, and I need to know if I'll damage the trans if I leave it this way.

Ok. Just read your moniker. 5.3L with 6L80, so a conversion. Sounds odd that no start/run power for remote start (oversight on conversion harness?). Would imagine GM normally runs start/run power to the trans for remote start in factory cars.

:cheers:

[PSWired]

Ok. Just read your moniker. 5.3L with 6L80, so a conversion. Sounds odd that no start/run power for remote start (oversight on conversion harness?). Would imagine GM normally runs start/run power to the trans for remote start in factory cars.

:cheers:

Yes, it was an oversight on my part. There was no conversion harness, the bus I put the new fuse for the transmission on was an ACC bus and not an IGN bus. The wiring is hard to access now that the instrument panel is back in place, so I wanted to make sure this is absolutely necessary before I go back in and re-do it.