Whatever Chrysler attached to V6s in the early 1990s. My mother and two of my bosses all had those fail early. Actually, my mother's didn't totally fail, but was intermittently shifting funny when she traded it in, just in time.
The junkiest automatic transmission ever manufactured?
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Originally Posted by bullwinkle
I'll do the best-
Chrysler A-727 Torqueflite
Ford C6
GM Turbo 400
All of these could even handle RV duty, I had a 727 in an 11,000 pound Class A (1973 with a 440-3 big block), and it handled flawlessly. Unfortunately the addition of overdrive to all of them seemed to cause problems (47RE, E4OD, 4L80/E).
Those were good!
The worst from my car selling days, the units Honda used in the V6 Accords, and Odyssey mini vans during my 2001-2003 run selling them, new and used. Many failed with less than 40K miles on them. Lots of complaining customers.
I'll do the best-
Chrysler A-727 Torqueflite
Ford C6
GM Turbo 400
All of these could even handle RV duty, I had a 727 in an 11,000 pound Class A (1973 with a 440-3 big block), and it handled flawlessly. Unfortunately the addition of overdrive to all of them seemed to cause problems (47RE, E4OD, 4L80/E).
Those were good!
The worst from my car selling days, the units Honda used in the V6 Accords, and Odyssey mini vans during my 2001-2003 run selling them, new and used. Many failed with less than 40K miles on them. Lots of complaining customers.
OVERKILL
$100 Site Donor 2021
Originally Posted by demarpaint
Originally Posted by bullwinkle
I'll do the best-
Chrysler A-727 Torqueflite
Ford C6
GM Turbo 400
All of these could even handle RV duty, I had a 727 in an 11,000 pound Class A (1973 with a 440-3 big block), and it handled flawlessly. Unfortunately the addition of overdrive to all of them seemed to cause problems (47RE, E4OD, 4L80/E).
Those were good!
The worst from my car selling days, the units Honda used in the V6 Accords, and Odyssey mini vans during my 2001-2003 run selling them, new and used. Many failed with less than 40K miles on them. Lots of complaining customers.
Yup, these. Absolute garbage.
Originally Posted by bullwinkle
I'll do the best-
Chrysler A-727 Torqueflite
Ford C6
GM Turbo 400
All of these could even handle RV duty, I had a 727 in an 11,000 pound Class A (1973 with a 440-3 big block), and it handled flawlessly. Unfortunately the addition of overdrive to all of them seemed to cause problems (47RE, E4OD, 4L80/E).
Those were good!
The worst from my car selling days, the units Honda used in the V6 Accords, and Odyssey mini vans during my 2001-2003 run selling them, new and used. Many failed with less than 40K miles on them. Lots of complaining customers.
Yup, these. Absolute garbage.
Originally Posted by DoubleWasp
Originally Posted by Gasbuggy
Originally Posted by DoubleWasp
Hard to beat the AXOD, but I'm gonna throw 700R4 on to the pile.
The early Ford 4R70 definitely belongs there, as well as it's AOD predecessor.
Anything Jatco that came in a Mazda.
LOL @ 700R4. Maybe the earliest 80s 27 spline. I've seen so many last so long in all itterations. It still lives as the 6l45/50
Originally Posted by madRiver
Those 3 speed junk boxes coupled to a 4 cyl economy car from 1980's thru 2000's. All of them abymsmal.
Neon, cavalier , Corolla, Subie.
4 speed -6 speeds solved so many issues. 8-10 mixed with stars and zeros.
TH125 was a decent trans. I have an original one still kicking in a cavalier with over 300,000 miles.
700R4 was a well known eater of the 3-4 clutch. Decent amount of them never saw 70k miles.
Technically, it doesn't live on, since it's been subject to huge engineering revisions since then and is no longer called the 700R4 as a result.
So your opinion of the 4l60E is different?
Originally Posted by Gasbuggy
Originally Posted by DoubleWasp
Hard to beat the AXOD, but I'm gonna throw 700R4 on to the pile.
The early Ford 4R70 definitely belongs there, as well as it's AOD predecessor.
Anything Jatco that came in a Mazda.
LOL @ 700R4. Maybe the earliest 80s 27 spline. I've seen so many last so long in all itterations. It still lives as the 6l45/50
Originally Posted by madRiver
Those 3 speed junk boxes coupled to a 4 cyl economy car from 1980's thru 2000's. All of them abymsmal.
Neon, cavalier , Corolla, Subie.
4 speed -6 speeds solved so many issues. 8-10 mixed with stars and zeros.
TH125 was a decent trans. I have an original one still kicking in a cavalier with over 300,000 miles.
700R4 was a well known eater of the 3-4 clutch. Decent amount of them never saw 70k miles.
Technically, it doesn't live on, since it's been subject to huge engineering revisions since then and is no longer called the 700R4 as a result.
So your opinion of the 4l60E is different?
Originally Posted by David1
Wait Wait... My 2002 Honda Accord has 250K miles.. I bought it at least 6 years ago from the person whom bought the car new. It was a 1 owner A title. This is as far as I know the orginal transmission. BX7A-1 it says on trans.. I bought the car with 168K on it. The car now has over 250K. Now I will admit you really have to maintain the [censored] outta them... I do a drain and fill on every 3rd oil change.. However I do no think they are the worst.. I know they are not bullet proof but I would not call the them a bad tranny... At least the bx7a-1.... I know there are some that i heard horror stories about.. That they went bad after 30K miles on them but I think Honda fixed the problem..
Perhaps one of the other Honda V6 trannys.. i know they had a few ....
They were improving the V6 trans every model year and sometimes mid model year. Through 2006 they came with 3/4 and 4/5 shift sensors that went bad before 100k; Honda dealers were so conditioned to declaring V6 transmission death that many were condemned when the fix was simple, and cheap (about like an easy spark plug change for each sensor).
Wait Wait... My 2002 Honda Accord has 250K miles.. I bought it at least 6 years ago from the person whom bought the car new. It was a 1 owner A title. This is as far as I know the orginal transmission. BX7A-1 it says on trans.. I bought the car with 168K on it. The car now has over 250K. Now I will admit you really have to maintain the [censored] outta them... I do a drain and fill on every 3rd oil change.. However I do no think they are the worst.. I know they are not bullet proof but I would not call the them a bad tranny... At least the bx7a-1.... I know there are some that i heard horror stories about.. That they went bad after 30K miles on them but I think Honda fixed the problem..
Perhaps one of the other Honda V6 trannys.. i know they had a few ....
They were improving the V6 trans every model year and sometimes mid model year. Through 2006 they came with 3/4 and 4/5 shift sensors that went bad before 100k; Honda dealers were so conditioned to declaring V6 transmission death that many were condemned when the fix was simple, and cheap (about like an easy spark plug change for each sensor).
Originally Posted by Gasbuggy
LOL @ 700R4. Maybe the earliest 80s 27 spline. I've seen so many last so long in all itterations. It still lives as the 6l45/50
The 700R4/4L60E shares nothing with 6L45E/6L50E, The entire 6LxxE lineup is a loose evolution of the 5L40E unit which shares some DNA with the TH180/3L30/4L30E as they ALL used Ravigneaux style gearsets. The Aluminum Powerglide also used this style of gearset.
700R4-4L60E/4T80E/440-T4/4T60/4T65E units use Simpson Split-Compound style gearsets,
3T40/TH200/2004R/TH250/325-4L/TH350/TH400/TH425/4L80E units use a Simpson Compound gearset ONLY for the 3-speeds, The 4-speed OD's on this list have an added Overdrive Carrier/Single gearset.
The 700R4 & 4L60E did have their fair share of issues, All can be fixed with a good rebuild unless you put to much power through it or tow to much weight aggressively. They are NOT a heavy duty unit!
LOL @ 700R4. Maybe the earliest 80s 27 spline. I've seen so many last so long in all itterations. It still lives as the 6l45/50
The 700R4/4L60E shares nothing with 6L45E/6L50E, The entire 6LxxE lineup is a loose evolution of the 5L40E unit which shares some DNA with the TH180/3L30/4L30E as they ALL used Ravigneaux style gearsets. The Aluminum Powerglide also used this style of gearset.
700R4-4L60E/4T80E/440-T4/4T60/4T65E units use Simpson Split-Compound style gearsets,
3T40/TH200/2004R/TH250/325-4L/TH350/TH400/TH425/4L80E units use a Simpson Compound gearset ONLY for the 3-speeds, The 4-speed OD's on this list have an added Overdrive Carrier/Single gearset.
The 700R4 & 4L60E did have their fair share of issues, All can be fixed with a good rebuild unless you put to much power through it or tow to much weight aggressively. They are NOT a heavy duty unit!
I nominate all the first gen 1980's American 4-speed overdrive automatics. And the CD4E. The A604 I had a lot of respect for, it was quite impressive for its time, but it had a horrible failure rate. All those transmissions made the old 3 speeds seem positively bulletproof.
Another nomination for the Chrysler 545RFE/65RFE. I never had a reliability issue, I just thought it was the DUMBEST geared transmission.
Super short 3.00:1 first gear, then a cliff up to the 1.67:1 2nd gear. And that stupid "kick down" or "2 prime" gear. 4th and 5th gears were both over drive. It was just never in the right gear for me.
What I don't get is in the Durango and Grand Cherokee (WD and WK2) the 5.7 HEMI's got those, while the v6 models got the W5A580. The same W5A580 they put behind SRT8 cars.
Super short 3.00:1 first gear, then a cliff up to the 1.67:1 2nd gear. And that stupid "kick down" or "2 prime" gear. 4th and 5th gears were both over drive. It was just never in the right gear for me.
What I don't get is in the Durango and Grand Cherokee (WD and WK2) the 5.7 HEMI's got those, while the v6 models got the W5A580. The same W5A580 they put behind SRT8 cars.
Originally Posted by clinebarger
Originally Posted by Gasbuggy
LOL @ 700R4. Maybe the earliest 80s 27 spline. I've seen so many last so long in all itterations. It still lives as the 6l45/50
The 700R4/4L60E shares nothing with 6L45E/6L50E, The entire 6LxxE lineup is a loose evolution of the 5L40E unit which shares some DNA with the TH180/3L30/4L30E as they ALL used Ravigneaux style gearsets. The Aluminum Powerglide also used this style of gearset.
700R4-4L60E/4T80E/440-T4/4T60/4T65E units use Simpson Split-Compound style gearsets,
3T40/TH200/2004R/TH250/325-4L/TH350/TH400/TH425/4L80E units use a Simpson Compound gearset ONLY for the 3-speeds, The 4-speed OD's on this list have an added Overdrive Carrier/Single gearset.
The 700R4 & 4L60E did have their fair share of issues, All can be fixed with a good rebuild unless you put to much power through it or tow to much weight aggressively. They are NOT a heavy duty unit!
I will stand corrected. I was told that the 6l45/50 evolved from the 700R4/4L60 and told the same about the 6L90 in my CTS-V evolving from the 4L80/TH400. At the time I searched a bit and noticed Wikipedia listed the 4L65/60 as the predecessors to the 6L45/50. I didn't look further than that.
Originally Posted by Gasbuggy
LOL @ 700R4. Maybe the earliest 80s 27 spline. I've seen so many last so long in all itterations. It still lives as the 6l45/50
The 700R4/4L60E shares nothing with 6L45E/6L50E, The entire 6LxxE lineup is a loose evolution of the 5L40E unit which shares some DNA with the TH180/3L30/4L30E as they ALL used Ravigneaux style gearsets. The Aluminum Powerglide also used this style of gearset.
700R4-4L60E/4T80E/440-T4/4T60/4T65E units use Simpson Split-Compound style gearsets,
3T40/TH200/2004R/TH250/325-4L/TH350/TH400/TH425/4L80E units use a Simpson Compound gearset ONLY for the 3-speeds, The 4-speed OD's on this list have an added Overdrive Carrier/Single gearset.
The 700R4 & 4L60E did have their fair share of issues, All can be fixed with a good rebuild unless you put to much power through it or tow to much weight aggressively. They are NOT a heavy duty unit!
I will stand corrected. I was told that the 6l45/50 evolved from the 700R4/4L60 and told the same about the 6L90 in my CTS-V evolving from the 4L80/TH400. At the time I searched a bit and noticed Wikipedia listed the 4L65/60 as the predecessors to the 6L45/50. I didn't look further than that.
Originally Posted by bullwinkle
I'll do the best-
Chrysler A-727 Torqueflite
Ford C6
GM Turbo 400
All of these could even handle RV duty, I had a 727 in an 11,000 pound Class A (1973 with a 440-3 big block), and it handled flawlessly. Unfortunately the addition of overdrive to all of them seemed to cause problems (47RE, E4OD, 4L80/E).
Really not fair. Those were the best but were also all the biggies from the 60's and 70's when things were naturally built better.
I'll do the best-
Chrysler A-727 Torqueflite
Ford C6
GM Turbo 400
All of these could even handle RV duty, I had a 727 in an 11,000 pound Class A (1973 with a 440-3 big block), and it handled flawlessly. Unfortunately the addition of overdrive to all of them seemed to cause problems (47RE, E4OD, 4L80/E).
Really not fair. Those were the best but were also all the biggies from the 60's and 70's when things were naturally built better.
Originally Posted by OVERKILL
Originally Posted by demarpaint
Originally Posted by bullwinkle
I'll do the best-
Chrysler A-727 Torqueflite
Ford C6
GM Turbo 400
All of these could even handle RV duty, I had a 727 in an 11,000 pound Class A (1973 with a 440-3 big block), and it handled flawlessly. Unfortunately the addition of overdrive to all of them seemed to cause problems (47RE, E4OD, 4L80/E).
Those were good!
The worst from my car selling days, the units Honda used in the V6 Accords, and Odyssey mini vans during my 2001-2003 run selling them, new and used. Many failed with less than 40K miles on them. Lots of complaining customers.
Yup, these. Absolute garbage.
Absolute garbage is an understatement. Total [it starts with an S] would be more like it. That's how they were often referred to in the shop.
Originally Posted by demarpaint
Originally Posted by bullwinkle
I'll do the best-
Chrysler A-727 Torqueflite
Ford C6
GM Turbo 400
All of these could even handle RV duty, I had a 727 in an 11,000 pound Class A (1973 with a 440-3 big block), and it handled flawlessly. Unfortunately the addition of overdrive to all of them seemed to cause problems (47RE, E4OD, 4L80/E).
Those were good!
The worst from my car selling days, the units Honda used in the V6 Accords, and Odyssey mini vans during my 2001-2003 run selling them, new and used. Many failed with less than 40K miles on them. Lots of complaining customers.
Yup, these. Absolute garbage.
The AXOD, AXOD-E and AX4S 4 speed transmission used in the following:
1991-2003 Ford Taurus
1991-2003 Mercury Sable
1991-1994 Lincoln Continental
1995-2000 Ford Windstar
The sychronous shift of the AXOD/AX4S caused them to wear out pretty quickly at low miles. Not to be confused with the AX4N (much, much better) due to non-sychronous. I believe the AX4N was designed for the SHO (V8 those years) which led to a more robust engineered (or over engineer for V6 model) design.
1991-2003 Ford Taurus
1991-2003 Mercury Sable
1991-1994 Lincoln Continental
1995-2000 Ford Windstar
The sychronous shift of the AXOD/AX4S caused them to wear out pretty quickly at low miles. Not to be confused with the AX4N (much, much better) due to non-sychronous. I believe the AX4N was designed for the SHO (V8 those years) which led to a more robust engineered (or over engineer for V6 model) design.
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Originally Posted by Gasbuggy
I will stand corrected. I was told that the 6l45/50 evolved from the 700R4/4L60 and told the same about the 6L90 in my CTS-V evolving from the 4L80/TH400. At the time I searched a bit and noticed Wikipedia listed the 4L65/60 as the predecessors to the 6L45/50. I didn't look further than that.
I thought the 5L-40E and 6L-45/50E were GM Strasbourg products for BMW and Cadillac/Holden applications?
I will stand corrected. I was told that the 6l45/50 evolved from the 700R4/4L60 and told the same about the 6L90 in my CTS-V evolving from the 4L80/TH400. At the time I searched a bit and noticed Wikipedia listed the 4L65/60 as the predecessors to the 6L45/50. I didn't look further than that.
I thought the 5L-40E and 6L-45/50E were GM Strasbourg products for BMW and Cadillac/Holden applications?
Originally Posted by nthach
Originally Posted by Gasbuggy
I will stand corrected. I was told that the 6l45/50 evolved from the 700R4/4L60 and told the same about the 6L90 in my CTS-V evolving from the 4L80/TH400. At the time I searched a bit and noticed Wikipedia listed the 4L65/60 as the predecessors to the 6L45/50. I didn't look further than that.
I thought the 5L-40E and 6L-45/50E were GM Strasbourg products for BMW and Cadillac/Holden applications?
That is correct, GM used the base design of the 6L40E/50E when they developed the 6L80E/90E. GM sold the Strasbourg plant to Punch Metals International shortly after buying back the plant from Motors Liquidation Company (bankruptcy). I believe the rights to the 6L40E/50E belong to Punch?
I don't think GM even uses the 6L40E/50E anymore as they have 8L45E's in the V6 Camaro, CTS, ATS, & CT6, The other 2 models that used the 6L40E/50E are either dead (STS) or redesigned to use a Transaxle (SRX).
Originally Posted by Gasbuggy
I will stand corrected. I was told that the 6l45/50 evolved from the 700R4/4L60 and told the same about the 6L90 in my CTS-V evolving from the 4L80/TH400. At the time I searched a bit and noticed Wikipedia listed the 4L65/60 as the predecessors to the 6L45/50. I didn't look further than that.
I thought the 5L-40E and 6L-45/50E were GM Strasbourg products for BMW and Cadillac/Holden applications?
That is correct, GM used the base design of the 6L40E/50E when they developed the 6L80E/90E. GM sold the Strasbourg plant to Punch Metals International shortly after buying back the plant from Motors Liquidation Company (bankruptcy). I believe the rights to the 6L40E/50E belong to Punch?
I don't think GM even uses the 6L40E/50E anymore as they have 8L45E's in the V6 Camaro, CTS, ATS, & CT6, The other 2 models that used the 6L40E/50E are either dead (STS) or redesigned to use a Transaxle (SRX).
Last edited:
Originally Posted by red7404
YES the Chrysler A-727 Torqueflite. is a very good trans.
The A727 is a very good unit, The only thing I don't like about them is the Synchronous 2-3 shift. The Front/Intermediate Band (2nd gear) has the be knocked-off at the same time the Direct Clutch (3rd gear) comes-on, This requires precise timing that's not possible in a pure hydraulic trans.
A Bind or Cut-Loose(Flare) will ALWAYS be there, A "ever-so-slight" Bind is the best you could ever hope to achieve. If the 2-3 shift on a A-727/46RE/47RE/48RE feels just slightly weird to you.....This is why! A completely "Clean" 2-3 shift is just not possible!
The GM 2004R/TH200/TH250/325-4L 2-3 shift's work on the same exact principle!
700R4/4L60E's work on a similar albeit different principle.....The 2-4 band has be knocked-off while the 3-4 Clutch comes-on during a 2-3 shift, Like the A727, A slight overlap of the 2 two Holding & Driving components is the best you can hope for. The difference being that it's not technically a Bind, The 2-4 Band & 3-4 Clutch "ON" at the same time is what gives you 4th Gear, So it goes like this on a 2-3 shift with a slight overlap........2nd4th3rd
Why a completely "Clean" 2-3 shift is not possible on this unit neither!
*A Cut-Loose(Flare) Synchronous issue on the other hand will burn frictions in a hurry!!!! Several 700R4/4L60E's suffered from this from the factory. And not as easy of a fix as a front band adjustment like A727 & it's derivatives.
The TH350/TH400/TH425/4L80E have a Non-Synchronous 2-3 shift......The Direct Drum has a Over-Running Clutch/Sprag/Mechanical Diode/Roller Clutch (Several names for the same part), This allows the Direct Clutches (3rd gear) to come-on while the Intermediate Clutch (2nd gear) can remain applied.
This type of unit has a completely clean 2-3 shift.
YES the Chrysler A-727 Torqueflite. is a very good trans.
The A727 is a very good unit, The only thing I don't like about them is the Synchronous 2-3 shift. The Front/Intermediate Band (2nd gear) has the be knocked-off at the same time the Direct Clutch (3rd gear) comes-on, This requires precise timing that's not possible in a pure hydraulic trans.
A Bind or Cut-Loose(Flare) will ALWAYS be there, A "ever-so-slight" Bind is the best you could ever hope to achieve. If the 2-3 shift on a A-727/46RE/47RE/48RE feels just slightly weird to you.....This is why! A completely "Clean" 2-3 shift is just not possible!
The GM 2004R/TH200/TH250/325-4L 2-3 shift's work on the same exact principle!
700R4/4L60E's work on a similar albeit different principle.....The 2-4 band has be knocked-off while the 3-4 Clutch comes-on during a 2-3 shift, Like the A727, A slight overlap of the 2 two Holding & Driving components is the best you can hope for. The difference being that it's not technically a Bind, The 2-4 Band & 3-4 Clutch "ON" at the same time is what gives you 4th Gear, So it goes like this on a 2-3 shift with a slight overlap........2nd4th3rd
Why a completely "Clean" 2-3 shift is not possible on this unit neither!
*A Cut-Loose(Flare) Synchronous issue on the other hand will burn frictions in a hurry!!!! Several 700R4/4L60E's suffered from this from the factory. And not as easy of a fix as a front band adjustment like A727 & it's derivatives.
The TH350/TH400/TH425/4L80E have a Non-Synchronous 2-3 shift......The Direct Drum has a Over-Running Clutch/Sprag/Mechanical Diode/Roller Clutch (Several names for the same part), This allows the Direct Clutches (3rd gear) to come-on while the Intermediate Clutch (2nd gear) can remain applied.
This type of unit has a completely clean 2-3 shift.
The A604 has issues in its first generation, but once warranty issues came up, Lee Iacocca rounded up the engineering team, asked what we can do to get this under control and found the solution. Allpar has a few good articles on the A604 and it's history.
I like all the old cast iron transmissions from the 50's and 60's. I agree with the 727 the 904 mopar held up ok , C4 and C6 ford, old BorgWarner automatics, I like both iron and aluminum power glides I have worked on many of both, the old hydramatics and 350 and 400, I can't say I am a fan of the 4L60 / 700R4's.
E4OD so far mine has held up in a 96, I see too many 70's through 2000's vehicles with transmission trouble, except the LS400 transmission and even the 2002 CLK430 Mercedes benz cars have well built transmissions, though electrical problems can crop up.
E4OD so far mine has held up in a 96, I see too many 70's through 2000's vehicles with transmission trouble, except the LS400 transmission and even the 2002 CLK430 Mercedes benz cars have well built transmissions, though electrical problems can crop up.
Originally Posted by clinebarger
Originally Posted by red7404
YES the Chrysler A-727 Torqueflite. is a very good trans.
The A727 is a very good unit, The only thing I don't like about them is the Synchronous 2-3 shift. The Front/Intermediate Band (2nd gear) has the be knocked-off at the same time the Direct Clutch (3rd gear) comes-on, This requires precise timing that's not possible in a pure hydraulic trans.
A Bind or Cut-Loose(Flare) will ALWAYS be there, A "ever-so-slight" Bind is the best you could ever hope to achieve. If the 2-3 shift on a A-727/46RE/47RE/48RE feels just slightly weird to you.....This is why! A completely "Clean" 2-3 shift is just not possible!
The GM 2004R/TH200/TH250/325-4L 2-3 shift's work on the same exact principle!
700R4/4L60E's work on a similar albeit different principle.....The 2-4 band has be knocked-off while the 3-4 Clutch comes-on during a 2-3 shift, Like the A727, A slight overlap of the 2 two Holding & Driving components is the best you can hope for. The difference being that it's not technically a Bind, The 2-4 Band & 3-4 Clutch "ON" at the same time is what gives you 4th Gear, So it goes like this on a 2-3 shift with a slight overlap........2nd4th3rd
Why a completely "Clean" 2-3 shift is not possible on this unit neither!
*A Cut-Loose(Flare) Synchronous issue on the other hand will burn frictions in a hurry!!!! Several 700R4/4L60E's suffered from this from the factory. And not as easy of a fix as a front band adjustment like A727 & it's derivatives.
The TH350/TH400/TH425/4L80E have a Non-Synchronous 2-3 shift......The Direct Drum has a Over-Running Clutch/Sprag/Mechanical Diode/Roller Clutch (Several names for the same part), This allows the Direct Clutches (3rd gear) to come-on while the Intermediate Clutch (2nd gear) can remain applied.
This type of unit has a completely clean 2-3 shift.
What did you think about the C6? Thanks.
Originally Posted by red7404
YES the Chrysler A-727 Torqueflite. is a very good trans.
The A727 is a very good unit, The only thing I don't like about them is the Synchronous 2-3 shift. The Front/Intermediate Band (2nd gear) has the be knocked-off at the same time the Direct Clutch (3rd gear) comes-on, This requires precise timing that's not possible in a pure hydraulic trans.
A Bind or Cut-Loose(Flare) will ALWAYS be there, A "ever-so-slight" Bind is the best you could ever hope to achieve. If the 2-3 shift on a A-727/46RE/47RE/48RE feels just slightly weird to you.....This is why! A completely "Clean" 2-3 shift is just not possible!
The GM 2004R/TH200/TH250/325-4L 2-3 shift's work on the same exact principle!
700R4/4L60E's work on a similar albeit different principle.....The 2-4 band has be knocked-off while the 3-4 Clutch comes-on during a 2-3 shift, Like the A727, A slight overlap of the 2 two Holding & Driving components is the best you can hope for. The difference being that it's not technically a Bind, The 2-4 Band & 3-4 Clutch "ON" at the same time is what gives you 4th Gear, So it goes like this on a 2-3 shift with a slight overlap........2nd4th3rd
Why a completely "Clean" 2-3 shift is not possible on this unit neither!
*A Cut-Loose(Flare) Synchronous issue on the other hand will burn frictions in a hurry!!!! Several 700R4/4L60E's suffered from this from the factory. And not as easy of a fix as a front band adjustment like A727 & it's derivatives.
The TH350/TH400/TH425/4L80E have a Non-Synchronous 2-3 shift......The Direct Drum has a Over-Running Clutch/Sprag/Mechanical Diode/Roller Clutch (Several names for the same part), This allows the Direct Clutches (3rd gear) to come-on while the Intermediate Clutch (2nd gear) can remain applied.
This type of unit has a completely clean 2-3 shift.
What did you think about the C6? Thanks.
- Status
