6l80e??
Nov 27, 2006 | 10:46 PM
#1
Thread Starter
Launching!
Joined: Sep 2004
Posts: 248
Likes: 0
From: Phoenix, AZ
6l80e??
doin a little research on a 6.0 LQ9 swap on my truck and was curious....will the new 6L80E tranny bolt up to the 6.0?
is the 6L80E gonna have any real advantages over the 4L80E?...perforamnce?..drivability?....anything?
is the 6L80E gonna have any real advantages over the 4L80E?...perforamnce?..drivability?....anything?
Nov 27, 2006 | 10:52 PM
#2
Driveability hell yes. The 2.48 1st gear in the 4L80E sucks ***** for launching. I think the 1st gear in the 6L80E is a 4.something. Not to mention a little better cruising gear if I remember correctly.
Nov 27, 2006 | 11:21 PM
#4
I think it will bolt up, controlling it will be another matter. The new trucks run off a CAN bus, which is a totally different architecture than the current PCM's. The 6L80E will require a standalone controller in the older trucks. Last I checked there was a company working on one, I think it was called Powertrain Control Solutions or something like that. Not sure what the status is on it.
Nov 27, 2006 | 11:34 PM
#5
Thread Starter
Launching!
Joined: Sep 2004
Posts: 248
Likes: 0
From: Phoenix, AZ
hmmm...well i am sure it will be a LONG while before i get this goin so hopefully this will be available by the time i can do this....i just wanna do my research now before i jump into anything and shoot myself in the foot
Nov 28, 2006 | 12:47 AM
#6
There have already been a few discussions about the 6L80-E for use in future swaps. The issues are as has been mentioned, but it can certainly handle the torque.
I've thought about a few more things though. The 6L80/90-E are clutch-to-clutch designs. This means that these transmission do not have the convensional sprags and roller clutches that we are used to having provide overrun. (Overrun occurs when you lift you foot off the gas in any gear and the engine is allowed to decellerate more quickly than the vehicle, in other words, the output "freewheels".) In a clutch-to-clutch transmission, it must upshift when you lift your foot or lifting your foot will result in engine braking. This has to be very precisely calibrated to match engine output or it will just feel like lifting the trottle on a stick shift without pressing the clutch pedal. There is no overrun provided by a mechanical diode such as a sprag or a roller clutch. In a 4L80-E, for example, there are two roller clutches and one sprag. These are all used for overrun and can be locked by overrun clutch packs. The 6L80/90-E does not have overrun clutches. (I think it might actually have one roller clutch or sprag for first gear only, but nothing beyond that.)
If an aftermarket controller should become available, programming it is going to be more tricky than any transmission calibration you've ever done because of the clutch-to-clutch architecture.
The Allison is also built this way.
Personally, I still feel that the best choice for a performance close-ratio bullet-proof transmission is a built 4L80/85-E... and maybe a Gear Vendors Overdrive behind it.
I've thought about a few more things though. The 6L80/90-E are clutch-to-clutch designs. This means that these transmission do not have the convensional sprags and roller clutches that we are used to having provide overrun. (Overrun occurs when you lift you foot off the gas in any gear and the engine is allowed to decellerate more quickly than the vehicle, in other words, the output "freewheels".) In a clutch-to-clutch transmission, it must upshift when you lift your foot or lifting your foot will result in engine braking. This has to be very precisely calibrated to match engine output or it will just feel like lifting the trottle on a stick shift without pressing the clutch pedal. There is no overrun provided by a mechanical diode such as a sprag or a roller clutch. In a 4L80-E, for example, there are two roller clutches and one sprag. These are all used for overrun and can be locked by overrun clutch packs. The 6L80/90-E does not have overrun clutches. (I think it might actually have one roller clutch or sprag for first gear only, but nothing beyond that.)
If an aftermarket controller should become available, programming it is going to be more tricky than any transmission calibration you've ever done because of the clutch-to-clutch architecture.
The Allison is also built this way.
Personally, I still feel that the best choice for a performance close-ratio bullet-proof transmission is a built 4L80/85-E... and maybe a Gear Vendors Overdrive behind it.
Nov 28, 2006 | 12:48 PM
#7
Originally Posted by James B.
There have already been a few discussions about the 6L80-E for use in future swaps. The issues are as has been mentioned, but it can certainly handle the torque.
I've thought about a few more things though. The 6L80/90-E are clutch-to-clutch designs. This means that these transmission do not have the convensional sprags and roller clutches that we are used to having provide overrun. (Overrun occurs when you lift you foot off the gas in any gear and the engine is allowed to decellerate more quickly than the vehicle, in other words, the output "freewheels".) In a clutch-to-clutch transmission, it must upshift when you lift your foot or lifting your foot will result in engine braking. This has to be very precisely calibrated to match engine output or it will just feel like lifting the trottle on a stick shift without pressing the clutch pedal. There is no overrun provided by a mechanical diode such as a sprag or a roller clutch. In a 4L80-E, for example, there are two roller clutches and one sprag. These are all used for overrun and can be locked by overrun clutch packs. The 6L80/90-E does not have overrun clutches. (I think it might actually have one roller clutch or sprag for first gear only, but nothing beyond that.)
If an aftermarket controller should become available, programming it is going to be more tricky than any transmission calibration you've ever done because of the clutch-to-clutch architecture.
The Allison is also built this way.
Personally, I still feel that the best choice for a performance close-ratio bullet-proof transmission is a built 4L80/85-E... and maybe a Gear Vendors Overdrive behind it.
I've thought about a few more things though. The 6L80/90-E are clutch-to-clutch designs. This means that these transmission do not have the convensional sprags and roller clutches that we are used to having provide overrun. (Overrun occurs when you lift you foot off the gas in any gear and the engine is allowed to decellerate more quickly than the vehicle, in other words, the output "freewheels".) In a clutch-to-clutch transmission, it must upshift when you lift your foot or lifting your foot will result in engine braking. This has to be very precisely calibrated to match engine output or it will just feel like lifting the trottle on a stick shift without pressing the clutch pedal. There is no overrun provided by a mechanical diode such as a sprag or a roller clutch. In a 4L80-E, for example, there are two roller clutches and one sprag. These are all used for overrun and can be locked by overrun clutch packs. The 6L80/90-E does not have overrun clutches. (I think it might actually have one roller clutch or sprag for first gear only, but nothing beyond that.)
If an aftermarket controller should become available, programming it is going to be more tricky than any transmission calibration you've ever done because of the clutch-to-clutch architecture.
The Allison is also built this way.
Personally, I still feel that the best choice for a performance close-ratio bullet-proof transmission is a built 4L80/85-E... and maybe a Gear Vendors Overdrive behind it.