4L80E Reference Material

[joecar]

http://forum.efilive.com/attachment.php?attachmentid=16096&d=1384029177




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[joecar]

http://forum.efilive.com/attachment.php?attachmentid=16097&d=1384029260




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[joecar]

http://forum.efilive.com/attachment.php?attachmentid=16098&d=1384029338



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[joecar]

http://forum.efilive.com/attachment.php?attachmentid=16099&d=1384029445





16099

[joecar]

http://forum.efilive.com/attachment.php?attachmentid=16100&d=1384029536



http://forum.efilive.com/attachment.php?attachmentid=16101&d=1384029559



16100 16101

[Redline Motorsports]

Some added info I just learned since we got our built 4L80E for our F-body race car;

Earlier 4L80E trannys have the cooler lines one of top of each other towards the front of the trans. Later years, and more desirable, have one in the front and one in the back. Apparently this significantly helps the pressure from dropping to the rear of the trans.

Howard

[Tydriver]

Some added info I just learned since we got our built 4L80E for our F-body race car;

Earlier 4L80E trannys have the cooler lines one of top of each other towards the front of the trans. Later years, and more desirable, have one in the front and one in the back. Apparently this significantly helps the pressure from dropping to the rear of the trans.

Howard

Correct, there are internal mods that can be performed on older trannys though, that will allow the planetarys to live on the older design transmissions.

The 4L80e = :rockon:

[joecar]

Here is the corrected truth table (the 4L80E HMTG shows incorrect columns D2 and D3):


http://forum.efilive.com/attachment.php?attachmentid=15619&d=1375370847




15619

[joecar]

http://forum.efilive.com/attachment.php?attachmentid=16102&d=1384029742




16102

[joecar]

Torque-Converters (http://forum.efilive.com/showthread.php?14555-Torque-Converters)

[mr.prick]

http://i235.photobucket.com/albums/ee259/whitespar/4L80wiring.jpg
http://i235.photobucket.com/albums/ee259/whitespar/4L80E_4L60E.jpg

[joecar]

To drive a 4L80E transmission from a 4L60E segment:
- discard the 3-2 control solenoid signal.
- drive the 4L80E 2-3 shift solenoid by using a relay to invert the 4L60E 2-3 shift solenoid signal;
- drive the 4L80E TCC PWM solenoid from the 4L60E TCC ON/OFF signal (discard the 4L60E TCC PWM signal), or see Alternative below;

Alternative (see posts #27 and #29 here (http://[/COLOR), thanks GNXClone (http://forum.efilive.com/member.php?8656-GNXClone)/Mike):
use the 4L60E TCC ON/OFF signal to control a relay which gates the 4L60E TCC PWM signal to the 4L80E TCC PWM solenoid:

http://forum.efilive.com/attachment.php?attachmentid=12216&d=1320530998&thumb=1 (http://forum.efilive.com/attachment.php?attachmentid=12216&d=1320530998)


TCC PWM warning:
the 4L60E may on occasion park the TCC PWM signal at 90% while the TCC is off,
this is the reason you don't want to drive the 4L80E TCC PWM solenoid solenoid directly from the 4L60E TCC PWM signal signal
(i.e. use a relay as Alternative says, or use the ON/OFF signal).

Note:
The F-car 4L60E segments keep the TCC locked on closed throttle decel (until vss goes below the unlock curve).
The Truck 4L80E segments (there are no 4L80E car segments) unlock the TCC on closed throttle.

To invert the 2-3 shift signal:
relay is connected as follows:
- the relay control coil is connected between 12V and the 2-3 shift solenoid signal from the PCM,
- the NC (off) relay contact goes to GND,
- the NO (on) relay contact goes to 12V,
- the swinging/gated contact goes to the 2-3 shift solenoid signal in the trans,

i.e. so when the PCM has the signal off (12V) the relay turns it on (GND), and vice-versa.


Also:
need to provide wiring to input 4L80E ISS signal into PCM.

[FPSeth]

Any ideas on what shift pressures should read? I know you can tap in with a manual gauge on 1/8 npt port on the mid/front of the drivers side, but for performance (drag racing, heavy vehicles etc..) use what pressures are we looking for?

[joecar]

Manual gauge on line tap port on side of case:
D: 80-230 psi (more as throttle/load increases);
R: 150 psi;

(as stated in Service Manual and any advanced trans repair manual)

For performance/heavy the minimum value in D is higher.

[LS-SWAPPER]

http://i235.photobucket.com/albums/ee259/whitespar/4L80wiring.jpg
http://i235.photobucket.com/albums/ee259/whitespar/4L80E_4L60E.jpg

I am in the middle of doing this. Using a 4l60e harness on a 4L80e trans with the 80e segment. My question is about pin T that the 60 has but the 80 doesn't have. Apparently it's not big deal and all I'm supposed to do is remove it from the harness for this application, but I'm curious what is different about these two trans in this regard? It comes across that the 60e has a tcc on/off "switch" wire, but the 80e doesn't...that seems odd. Can anybody shed some light on this just for my general knowledge/curiosity?

[joecar]

4L60E: has TCC PWM and TCC On/Off.

4L80E: has TCC PWM only.


That is just how they were designed.


4L60E operation:
PCM ramps up TCC PWM and enables TCC On/Off to lock the TCC.
While TCC is unlocked, PCM may ramp TCC PWM up to 90% just for the heck of it (maybe to clean the hydraulic circuit).

4L80E operation:
PCM ramps up TCC PWM to lock the TCC.

[joecar]

Remove pins T and U.

[LS-SWAPPER]

Remove pins T and U.

Yes, I agree.

On another note, the wire color in your charts are totally different than mine. The first pic is a 2001 silverado 1500 4L60e harness, and in the second pic the same connector is on the left (it was dirty in this pic, clean in the first one). On the right is a 4L80e connector from a 2006 silverado 2500. Notice the "M" pin wire is a different color between the two. Thought this might help some people searching through the forum like I was doing.
1569915700

[hog]

4L60E: has TCC PWM and TCC On/Off.

4L80E: has TCC PWM only.


That is just how they were designed.


4L60E operation:
PCM ramps up TCC PWM and enables TCC On/Off to lock the TCC.
While TCC is unlocked, PCM may ramp TCC PWM up to 90% just for the heck of it (maybe to clean the hydraulic circuit).

4L80E operation:
PCM ramps up TCC PWM to lock the TCC.
4l80e has always been PWM only from 1991?

I know in the 4l60e there is PWM, ECCC(EC3) and on/off as there were 3 differnt TCC materials.
Didnt realize 4l80e was PWM ONLY.

peace
Hog

[Supercharged111]

Remove pins T and U.

I just swapped pins S and U. I don't recall T or U existing on the transmission, so no reason to remove them when they're potentially plugging a leak (trans plugs like to leak, just replaced my harness for this).

[joecar]

Here is some 4L80E info: sloppywiki/everything-ls/4l80e-info (https://sites.google.com/site/sloppywiki/everything-ls/4l80e-info)

[joecar]

PT shift table relationships:

basic relationships:
1->2 curve should be above 2->1 curve;
2->3 curve should be above 3->2 curve;
3->4 curve should be above 4->3 curve;

additional relationships:
3->2 curve should be above 1->2 curve;
4->3 curve should be above 2->3 curve;

this can be summarized as: the curves cannot cross anywhere;

if they cross anywhere, then you will not be able to predict what gear the PCM selects when the operating point hits the cross.