Need info on a 6l90 trans

[chevyguy_72]

I am looking at ordering a new 6l90 trans from GM...
Prob is they have literally about 30 part numbers for 6L90 transmissions ranging from 2009-present year and ranging from Truck, van, Camaro ZL1, CTS-v, Avalanche, etc as far as what they are out of...
I like the truck ones because they still have the slip shaft output shaft similar to turbo 400 etc... the camaro ones have a solid output shaft and you have to get a drive shaft with the slip shaft built in (Similar to Hart Rod) also there is a difference in the oil pan (height/capacity) but those seem to be interchangable...

I am trying to research the differences from there... the only thing i or the dealer has found is that the valve body seems to be a different part number from the truck vs ZL1/CTS-V Trans...

Anyone else might have any input or some solid places to look for info?
Thanks

[fastpace]

The issue with the 6 speeds is that the have an internal TCU which syncs with the ECU. So people have had a lot of issues with pairing up a speed with an engine combo that it didn't originally come with since you'll need the ECU that is compatible for communication. Your best bet is to call Speartech they seem to have the most information information and experience with 6 speed control.

[chevyguy_72]

I have a E38 PCM with 2010 L92 ... it should work as this originally had a 6l80 behind it...

[BR3W CITY]

Pretty sure the cars have the TuTd feature, where the trucks weren't programmed for that.

[chevyguy_72]

Originally Posted by BR3W CITY

Pretty sure the cars have the TuTd feature, where the trucks weren't programmed for that.

i believe you are talking paddle shifts or electronic shift buttons...
On the trucks its just a button built into the column shifter to allow you to shift up and down. I currently have that feature in my avalanche w/6l80

[BR3W CITY]

Flappy paddles!


funny you say that about the avalanche, I've never owned a chevy with an LS....that was SUPPOSED to have an LS in it. Go Figure.

[chevyguy_72]

That was what you were talking about right??
I have been told that the Tow/haul mode and sport mode are the same function just different parameters.

Originally Posted by BR3W CITY

Flappy paddles!


funny you say that about the avalanche, I've never owned a chevy with an LS....that was SUPPOSED to have an LS in it. Go Figure.

[BR3W CITY]

I never tried the tow mode on them, can you actually sequentially select gears?

[chevyguy_72]

You mean on the avalanche?
Yes you put the physical shifter into the "M" position and then there is a little "=" or "-" to manually shift the truck... i will take a pic at lunch...

[Hart_Rod]

Originally Posted by BR3W CITY

I never tried the tow mode on them, can you actually sequentially select gears?

Originally Posted by chevyguy_72

You mean on the avalanche?
Yes you put the physical shifter into the "M" position and then there is a little "=" or "-" to manually shift the truck... i will take a pic at lunch...

On the truck/suv's when you are in M (manual mode), if you have 5th gear selected the transmission will go no higher than 5th gear. When you stop at a light it will automatically downshift to 1st and then automatically shift back up to 5th (or the highest gear that you have selected).

In the camaros/corvettes when you are in M (Sport mode), until you touch the paddle shifters, the car will still shift automatically, however it shifts are much crispier. When you first use the paddle shifters, now you have taken over the shifting of the transmission "manually". When you come to a stop, the transmission will down shift automatically (it stops a 2nd gear you have to paddle shift it to 1st gear), but at a slower rate than it would normally downshift. This allows you a little more freedom to control the down shifts. When you take off, it will not upshift until you hit the paddle shifters. There are also some protections within the programming that will prevent you from doing certain downshifts. It will try to protect the motor and transmission. With that being said, I think you can remove the protection within the tune (at your own peril of course...).

As far as the tow/haul mode on trucks. It also changes the shift time (raises the rpm for the shift) and adjusts the lock/up of the torque converter.

I do think you can change the tune's in the trucks TCM to work like the cars, but I'm not 100% sure on that...


Back to the 6L80/6L90. First, there are differences in the years on the wiring and how the TCM work. I would do a LOT of research before I purchased one! Mismatches between the ECM and TCM seem to cause about 99% of the problems I have read about with these swaps. I just want you to be aware.

As far as the tranny pan, the 6L80 tranny/pan is shorter than the 6L90 front to rear. The cadillac ctsv pan I used is the thinnest pan (top to bottom) that you can put on the 6L80. No one makes a thin pan for the 6L90. However, I have seen guys modify the 6L80 ctsv pan to fit the 6L90....

Just some food for thought and some stuff I have learned throughout my swap process. I am by no means and expert on any of this, but will share my experiences if you have any more questions. John a Speartech is a good guy to talk to about this. He also sells 6L80/6L90s that are ready for swap.

[chevyguy_72]

i shot them a email... i will wait for reply
Thanks

Originally Posted by Hart_Rod

On the truck/suv's when you are in M (manual mode), if you have 5th gear selected the transmission will go no higher than 5th gear. When you stop at a light it will automatically downshift to 1st and then automatically shift back up to 5th (or the highest gear that you have selected).

In the camaros/corvettes when you are in M (Sport mode), until you touch the paddle shifters, the car will still shift automatically, however it shifts are much crispier. When you first use the paddle shifters, now you have taken over the shifting of the transmission "manually". When you come to a stop, the transmission will down shift automatically (it stops a 2nd gear you have to paddle shift it to 1st gear), but at a slower rate than it would normally downshift. This allows you a little more freedom to control the down shifts. When you take off, it will not upshift until you hit the paddle shifters. There are also some protections within the programming that will prevent you from doing certain downshifts. It will try to protect the motor and transmission. With that being said, I think you can remove the protection within the tune (at your own peril of course...).

As far as the tow/haul mode on trucks. It also changes the shift time (raises the rpm for the shift) and adjusts the lock/up of the torque converter.

I do think you can change the tune's in the trucks TCM to work like the cars, but I'm not 100% sure on that...


Back to the 6L80/6L90. First, there are differences in the years on the wiring and how the TCM work. I would do a LOT of research before I purchased one! Mismatches between the ECM and TCM seem to cause about 99% of the problems I have read about with these swaps. I just want you to be aware.

As far as the tranny pan, the 6L80 tranny/pan is shorter than the 6L90 front to rear. The cadillac ctsv pan I used is the thinnest pan (top to bottom) that you can put on the 6L80. No one makes a thin pan for the 6L90. However, I have seen guys modify the 6L80 ctsv pan to fit the 6L90....

Just some food for thought and some stuff I have learned throughout my swap process. I am by no means and expert on any of this, but will share my experiences if you have any more questions. John a Speartech is a good guy to talk to about this. He also sells 6L80/6L90s that are ready for swap.