Hydra-Matic 6L80 Auto #05-07-30-023

[Philip Lochner]

Hi all

Now that I have my V12's sorted it would be so nice to have a proper gearbox behind them! 4sp is just not worth the effort IMHO. A 6sp is the least I would go for.

So, would Megashift (at current level of functionality) be able to control the 6L80 as found in
2006 Cadillac STS-V, XLR-V
2006 Chevrolet Corvette?

I have some info attached hoping that would enable the fundi's to answer my question.

[Bernard Fife]

Philip,

Maybe. There appear to be 6 solenoids on the trans, and current 2.111 code has up to 6 shift outputs. But it depends on the PWM requirements of those solenoids, among other things, so you will need to do more digging.

The upcoming 2.120 code (due in a week or so) will have up to 7 outputs to control the solenoids (some will require hardware mods), and 2 of these have user variable PWM depending on one of load, speed, rpm, temperature, or gear. Whether that is needed here I can't say from the doc provided.

However, a more serious impediment with the 6L60E is that the trans controller is built right into the transmission itself, and this would need to be removed and leads run to the devices directly, which likely would not be a trivial task. The 6L60E is also a physically very large transmission, so retrofits are often difficult without hacking the car to pieces.

Lance.

[MSEngineering]

Philip,

Maybe. There appear to be 6 solenoids on the trans, and current 2.111 code has up to 6 shift outputs. But it depends on the PWM requirements of those solenoids, among other things, so you will need to do more digging.

The upcoming 2.120 code (due in a week or so) will have up to 7 outputs to control the solenoids (some will require hardware mods), and 2 of these have user variable PWM depending on one of load, speed, rpm, temperature, or gear. Whether that is needed here I can't say from the doc provided.

However, a more serious impediment with the 6L60E is that the trans controller is built right into the transmission itself, and this would need to be removed and leads run to the devices directly, which likely would not be a trivial task. The 6L60E is also a physically very large transmission, so retrofits are often difficult without hacking the car to pieces.

Lance.

That TSB really on the surface there leaves out a lot of information, but it's just a TSB after all.

I have the service manual to this transmission there are actually 8 solenoids ( unless you purposely left out shift solenoids 1 & 2). All of the 6 are PWM solenoids and not on/off solenoids like shift shift solenoids 1&2. The Manual states all clutch pressure control solenoids are commanded to a specific control pressure.

Also there is a IMS (internal mode switch) which is connected in this fashion : Gear lever(electronic & mechanical) -> IMS -> TCM the TCM has a CAN HI and CAN LOW. So it's best to do away with the TCM in there all the solenoids have 2 prongs on them.

There is a speed sensor input and output assembly, the input reads the speed of 1-2-3-4 and 3-5-R clutch and the other output reads the output shaft housing, both state the TCM use this signal to determine line pressure, shift timing, vehicle speed and gear ratio.

I would like to get some development going on with this transmission I have a 6L90E I'm want to use with a Diesel application but the needs a bit more capability and references.