4L80E clutches, can someone explain them? the sprag?
4L80E clutches, can someone explain them? the sprag?
09-10-2006 | 04:08 AM
#2
I can do this...
Forward Clutches
This clutch pack engages for all forward movement. It is not engaged in Park, Neutral, or Reverse. In the forward clutch pack the steel discs are splined to the forward clutch housing (rotating assembly) on the outside and the friction discs are splined to a hub connected to the main shaft in the inside. With only the Forward Clutch applied you get first gear.
Intermediate Clutches
This clutch pack gives you second gear. It's the "intermediate" gear between low and direct. It is engaged for second, third, and fourth gears. In the intermediate clutch pack the steel discs are splined on their outside diameters to the case. The friction discs are splined on their inside diameters to the outer race of the sprag on the aft side of the direct clutch housing.
Direct Clutches
Direct in transmission speak generally means 1:1 direct drive, no underdrive, no overdrive. The direct clutch pack is applied for third, fourth, and reverse. The outside diameter of the steel discs are splined to the direct clutch housing (rotating assembly) and the friction discs are splined on their inside diameters to the hub on the aft side of the forward clutch housing. The direct clutch housing itself is connected to the sun gear shaft, which is a hollow shaft that the main shaft rotates within.
Fourth Clutches
This pack gives you overdrive. The overdrive (4th) clutch pack in the 4L80-E. The overdrive clutch pack controls its own planetary gear set (huge) in the front of the 4L80-E completely independent of the other two for the other gears. The overdrive clutch steel discs are splined to the transmission case and the friction discs are splined on their internal diameters to the overrun clutch housing.
Overrun Clutches
The overrun clutches provide a backward power flow (engine braking) when the selctor is in 1, 2, or 3. This clutch pack cannot be used in overdrive (that would cause a bind) or to engine brake in reverse. The outside diameter of the overrun clutch steel discs are splined to the overrun clutch housing and the inside diameters of the friction discs are splined to the overdrive planet carrier assembly and connected to the turbine (input) shaft.
Sprags and Roller Clutches
Sprags and Roller clutches do essentially the same thing. They are mechanical diodes. They are mechanical-only, no friction materials in these. They allow rotation to be transfered from the inner part to the outer part in only one direction. rotational torque in the oposite direction results in freewheel. There are two roller clutches in the 4L80-E, one in the overdrive assembly, the other (called a low roller clutch) is between the reaction carrier assembly and the center support. When the overdrive clutches are not applied, torque transfers from the holding direction of the roller clutch. Let your foot off the pedal when the gear selector is in Drive (4) and the trans is in first, second, or third gear and engine RPM will fall because the roller clutch begins to freewheel. In fourth gear the roller clutch is overrun by the gear ratio of fourth and therefore serves no pupose in fourth gear. The function of the overrun clutches metioned above is to prevent the roller clutch from freewheeling, essentially locking those two rotating components together (roller clutch housing and the overdrive carrier).
A sprag in mechanically different and capable of holding more torque than a roller clutch because it's more self energizing and has more elements of contact. The one sprag in the 4L80-E is located between the direct clutch housing and the hub that the intermediate clutch is splined to.
You might notice, if you're looking at a rebuild kit, that the direct and forward clutch discs are identical. The frictions are but the steel plates may have some slight differences in oil drainoff passages.
I hope that answers your questions!
(Can we call it even now for your help on the Metallic Magnaflow cats? lol)
Forward Clutches
This clutch pack engages for all forward movement. It is not engaged in Park, Neutral, or Reverse. In the forward clutch pack the steel discs are splined to the forward clutch housing (rotating assembly) on the outside and the friction discs are splined to a hub connected to the main shaft in the inside. With only the Forward Clutch applied you get first gear.
Intermediate Clutches
This clutch pack gives you second gear. It's the "intermediate" gear between low and direct. It is engaged for second, third, and fourth gears. In the intermediate clutch pack the steel discs are splined on their outside diameters to the case. The friction discs are splined on their inside diameters to the outer race of the sprag on the aft side of the direct clutch housing.
Direct Clutches
Direct in transmission speak generally means 1:1 direct drive, no underdrive, no overdrive. The direct clutch pack is applied for third, fourth, and reverse. The outside diameter of the steel discs are splined to the direct clutch housing (rotating assembly) and the friction discs are splined on their inside diameters to the hub on the aft side of the forward clutch housing. The direct clutch housing itself is connected to the sun gear shaft, which is a hollow shaft that the main shaft rotates within.
Fourth Clutches
This pack gives you overdrive. The overdrive (4th) clutch pack in the 4L80-E. The overdrive clutch pack controls its own planetary gear set (huge) in the front of the 4L80-E completely independent of the other two for the other gears. The overdrive clutch steel discs are splined to the transmission case and the friction discs are splined on their internal diameters to the overrun clutch housing.
Overrun Clutches
The overrun clutches provide a backward power flow (engine braking) when the selctor is in 1, 2, or 3. This clutch pack cannot be used in overdrive (that would cause a bind) or to engine brake in reverse. The outside diameter of the overrun clutch steel discs are splined to the overrun clutch housing and the inside diameters of the friction discs are splined to the overdrive planet carrier assembly and connected to the turbine (input) shaft.
Sprags and Roller Clutches
Sprags and Roller clutches do essentially the same thing. They are mechanical diodes. They are mechanical-only, no friction materials in these. They allow rotation to be transfered from the inner part to the outer part in only one direction. rotational torque in the oposite direction results in freewheel. There are two roller clutches in the 4L80-E, one in the overdrive assembly, the other (called a low roller clutch) is between the reaction carrier assembly and the center support. When the overdrive clutches are not applied, torque transfers from the holding direction of the roller clutch. Let your foot off the pedal when the gear selector is in Drive (4) and the trans is in first, second, or third gear and engine RPM will fall because the roller clutch begins to freewheel. In fourth gear the roller clutch is overrun by the gear ratio of fourth and therefore serves no pupose in fourth gear. The function of the overrun clutches metioned above is to prevent the roller clutch from freewheeling, essentially locking those two rotating components together (roller clutch housing and the overdrive carrier).
A sprag in mechanically different and capable of holding more torque than a roller clutch because it's more self energizing and has more elements of contact. The one sprag in the 4L80-E is located between the direct clutch housing and the hub that the intermediate clutch is splined to.
You might notice, if you're looking at a rebuild kit, that the direct and forward clutch discs are identical. The frictions are but the steel plates may have some slight differences in oil drainoff passages.
I hope that answers your questions!
(Can we call it even now for your help on the Metallic Magnaflow cats? lol)
09-10-2006 | 09:08 AM
#3
09-10-2006 | 11:18 AM
#4
Thread Starter
what a rush!
iTrader: (8)
Joined: Feb 2004
Posts: 17,611
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From: Las Vegas, NV
Originally Posted by James B.
I can do this...
Forward Clutches
This clutch pack engages for all forward movement. It is not engaged in Park, Neutral, or Reverse. In the forward clutch pack the steel discs are splined to the forward clutch housing (rotating assembly) on the outside and the friction discs are splined to a hub connected to the main shaft in the inside. With only the Forward Clutch applied you get first gear.
Intermediate Clutches
This clutch pack gives you second gear. It's the "intermediate" gear between low and direct. It is engaged for second, third, and fourth gears. In the intermediate clutch pack the steel discs are splined on their outside diameters to the case. The friction discs are splined on their inside diameters to the outer race of the sprag on the aft side of the direct clutch housing.
Direct Clutches
Direct in transmission speak generally means 1:1 direct drive, no underdrive, no overdrive. The direct clutch pack is applied for third, fourth, and reverse. The outside diameter of the steel discs are splined to the direct clutch housing (rotating assembly) and the friction discs are splined on their inside diameters to the hub on the aft side of the forward clutch housing. The direct clutch housing itself is connected to the sun gear shaft, which is a hollow shaft that the main shaft rotates within.
Fourth Clutches
This pack gives you overdrive. The overdrive (4th) clutch pack in the 4L80-E. The overdrive clutch pack controls its own planetary gear set (huge) in the front of the 4L80-E completely independent of the other two for the other gears. The overdrive clutch steel discs are splined to the transmission case and the friction discs are splined on their internal diameters to the overrun clutch housing.
Overrun Clutches
The overrun clutches provide a backward power flow (engine braking) when the selctor is in 1, 2, or 3. This clutch pack cannot be used in overdrive (that would cause a bind) or to engine brake in reverse. The outside diameter of the overrun clutch steel discs are splined to the overrun clutch housing and the inside diameters of the friction discs are splined to the overdrive planet carrier assembly and connected to the turbine (input) shaft.
Sprags and Roller Clutches
Sprags and Roller clutches do essentially the same thing. They are mechanical diodes. They are mechanical-only, no friction materials in these. They allow rotation to be transfered from the inner part to the outer part in only one direction. rotational torque in the oposite direction results in freewheel. There are two roller clutches in the 4L80-E, one in the overdrive assembly, the other (called a low roller clutch) is between the reaction carrier assembly and the center support. When the overdrive clutches are not applied, torque transfers from the holding direction of the roller clutch. Let your foot off the pedal when the gear selector is in Drive (4) and the trans is in first, second, or third gear and engine RPM will fall because the roller clutch begins to freewheel. In fourth gear the roller clutch is overrun by the gear ratio of fourth and therefore serves no pupose in fourth gear. The function of the overrun clutches metioned above is to prevent the roller clutch from freewheeling, essentially locking those two rotating components together (roller clutch housing and the overdrive carrier).
A sprag in mechanically different and capable of holding more torque than a roller clutch because it's more self energizing and has more elements of contact. The one sprag in the 4L80-E is located between the direct clutch housing and the hub that the intermediate clutch is splined to.
You might notice, if you're looking at a rebuild kit, that the direct and forward clutch discs are identical. The frictions are but the steel plates may have some slight differences in oil drainoff passages.
I hope that answers your questions!
(Can we call it even now for your help on the Metallic Magnaflow cats? lol)
Forward Clutches
This clutch pack engages for all forward movement. It is not engaged in Park, Neutral, or Reverse. In the forward clutch pack the steel discs are splined to the forward clutch housing (rotating assembly) on the outside and the friction discs are splined to a hub connected to the main shaft in the inside. With only the Forward Clutch applied you get first gear.
Intermediate Clutches
This clutch pack gives you second gear. It's the "intermediate" gear between low and direct. It is engaged for second, third, and fourth gears. In the intermediate clutch pack the steel discs are splined on their outside diameters to the case. The friction discs are splined on their inside diameters to the outer race of the sprag on the aft side of the direct clutch housing.
Direct Clutches
Direct in transmission speak generally means 1:1 direct drive, no underdrive, no overdrive. The direct clutch pack is applied for third, fourth, and reverse. The outside diameter of the steel discs are splined to the direct clutch housing (rotating assembly) and the friction discs are splined on their inside diameters to the hub on the aft side of the forward clutch housing. The direct clutch housing itself is connected to the sun gear shaft, which is a hollow shaft that the main shaft rotates within.
Fourth Clutches
This pack gives you overdrive. The overdrive (4th) clutch pack in the 4L80-E. The overdrive clutch pack controls its own planetary gear set (huge) in the front of the 4L80-E completely independent of the other two for the other gears. The overdrive clutch steel discs are splined to the transmission case and the friction discs are splined on their internal diameters to the overrun clutch housing.
Overrun Clutches
The overrun clutches provide a backward power flow (engine braking) when the selctor is in 1, 2, or 3. This clutch pack cannot be used in overdrive (that would cause a bind) or to engine brake in reverse. The outside diameter of the overrun clutch steel discs are splined to the overrun clutch housing and the inside diameters of the friction discs are splined to the overdrive planet carrier assembly and connected to the turbine (input) shaft.
Sprags and Roller Clutches
Sprags and Roller clutches do essentially the same thing. They are mechanical diodes. They are mechanical-only, no friction materials in these. They allow rotation to be transfered from the inner part to the outer part in only one direction. rotational torque in the oposite direction results in freewheel. There are two roller clutches in the 4L80-E, one in the overdrive assembly, the other (called a low roller clutch) is between the reaction carrier assembly and the center support. When the overdrive clutches are not applied, torque transfers from the holding direction of the roller clutch. Let your foot off the pedal when the gear selector is in Drive (4) and the trans is in first, second, or third gear and engine RPM will fall because the roller clutch begins to freewheel. In fourth gear the roller clutch is overrun by the gear ratio of fourth and therefore serves no pupose in fourth gear. The function of the overrun clutches metioned above is to prevent the roller clutch from freewheeling, essentially locking those two rotating components together (roller clutch housing and the overdrive carrier).
A sprag in mechanically different and capable of holding more torque than a roller clutch because it's more self energizing and has more elements of contact. The one sprag in the 4L80-E is located between the direct clutch housing and the hub that the intermediate clutch is splined to.
You might notice, if you're looking at a rebuild kit, that the direct and forward clutch discs are identical. The frictions are but the steel plates may have some slight differences in oil drainoff passages.
I hope that answers your questions!
(Can we call it even now for your help on the Metallic Magnaflow cats? lol)
09-10-2006 | 03:31 PM
#6
Originally Posted by moregrip
....did you ever get them installed?
They are holding up and working well.
If you need any pictures of any 4L80-E parts or assemblies, just ask. I took pictures of everything the first time I took one apart, and memorized them!
09-12-2006 | 07:52 PM
#7
so is there any ill side effects if you remove the overrun clutches. i believe that is what the builder did in my buds th350 for his drag car. it is fun you can be cruising in 3rd gear and put it in second and no one knows then hammer it. it is like a manual trans. but i have heard it will over spinn something??? and jack stuff up. when i get around to jacking with my 80 i wana pull it apart and do some stuff to it. but have not got a answer on this ??? but i realy like the characteristics of his th350 and would like something similar if capable. hell i contemplated a 350
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350's don't have overrun clutches. Maybe he left the band out!
09-13-2006 | 12:17 AM
#9
yea see i dont know jack about transmisions. so i guess that is what he did cuz we will be cruising at 1500 rpms and someone pulls up next to us you can down shift and it is almost like u put the clutch in on a manual and down shifted it then took off. i sound like a ricer or dumb a$$ but i dont know much about transmisions.
so what can be done with my 80?
so what can be done with my 80?
09-13-2006 | 02:18 AM
#10
Originally Posted by sleepersilverado
so is there any ill side effects if you remove the overrun clutches...