6 speed automatic transmission

Faults and Technical chat for the Corsa E
simon.billson.7
Posts: 4
Joined: Thu Aug 24, 2017 10:11 pm

6 speed automatic transmission

Post by simon.billson.7 » Thu Aug 24, 2017 10:55 pm

I've just bought a 66 plate corsa 1.4 (90) automatic. It works great and is amazingly economical. Can anyone tell me whether it is a torque converter unit or some kind of dual clutch system? I've not been able to find any information online or in the vehicle handbook. It's a 6 speed unit so I don't think it's an easytronic gearbox. Anybody got any idea?


Sent from my iPhone using Tapatalk


Moog70
Posts: 173
Joined: Wed Sep 14, 2016 8:34 am
Location: Warwickshire

Re: 6 speed automatic transmission

Post by Moog70 » Fri Aug 25, 2017 9:05 am

Im pretty sure its still just the ZF 'easytronic' type box that they were using back in Vectra''s 10 years ago! I'm happy to stand corrected, but if its any consolation, they are incredibly reliable if they in fact are, and will probably outlast the engine. They do not use a torque converter and are a single plate dry clutch.
Current - MY17 1.4T Energy 3 Door Persian Blue (with now useless heated steering wheel)
Gone - MY15 1.4i Excite 3 Door Deep Sea Blue (with brilliant heated steering wheel)


User avatar
Delboy_Lee
Posts: 855
Joined: Sat Feb 07, 2015 9:10 pm
Location: Lee-On-The-Solent

Re: 6 speed automatic transmission

Post by Delboy_Lee » Fri Aug 25, 2017 12:26 pm

This is information I have found on the Automatic Gear Box:

GM 6-Speed 6T30 MH9 Hydra-Matic Automatic Transmission:

The Hydra-Matic 6T30 (production code MH9) is a six-speed automatic transmission produced by General Motors for use in small front-wheel-drive vehicles with a transverse power train orientation. Developed in-house by General Motors, the Hydra-Matic 6T30 is part of the 6TXX family of transmissions that succeeded the 5TXX family. The 6T30 is the least robust unit in its family.

Six-speed automatic transmissions are integral to GM’s initiative to offer vehicles with excellent fuel economy. The Hydra-Matic 6T30 transmission delivers on that promise. It was designed for compact FWD applications and is part of GM’s family of technologically advanced, fuel-saving six-speed automatic transmissions. Shared traits between the 6TXX family – and other Hydra-Matic six-speeds is to reduce complexity, size and mass, including clutch-to-clutch operation that enables the six-speed to be packaged into approximately the same space as a four-speed automatic.
Because of the wide ratio spread, first gear is a very high ratio, which provides brisk acceleration from a stop. Sixth gear, however, is an overdrive ratio, which keeps the engine revolutions lower for highway cruising, reducing engine friction losses and optimizing fuel economy.
On-Axis Design
Instead of “folding” the transmission around the end of a transversely mounted engine, which has been one of the dominant GM transaxle design conventions, the 6T30 contains all of the gearing on the engine crankshaft centerline. The advantages of this layout enables a shorter overall vehicle length, more interior room and lower powertrain height.
Clutch-To-Clutch Shift Operation
Three planetary gearsets are used with three stationary clutches and two rotating clutches, which save space compared to freewheeling designs. Freewheeling mechanisms allow accurate timing between shifts, but also take up more space and add more components to the transmission. Through electronic controls, the clutch-to-clutch concept of the 6T30 delivers optimal shift timing.
Gear changes from second to sixth gear ratios are accomplished with a precise clutch-to-clutch action, where the clutch is engaged in one gear at exactly the same time it is released in another. The first-to-second upshift, however, is a freewheeling action, where the second gear clutch engages while the first gear one-way clutch spins freely. This allows a greater degree of smoothness at lower vehicle speeds.
Adaptive Shift Controls
Adaptive shift controls include automatic grade braking, which commands the transmission to remain in a lower gear if the vehicle is decelerating or coasting on a downgrade. This takes advantage of engine braking to prevent unwanted acceleration. This reduces the number of brake applies for the driver to brake during a hill descent. The control module receives input that monitors brake pedal usage, vehicle acceleration rate, throttle position, and even whether a trailer is connected to the vehicle.
Space-Saving Hyper-Elliptical Torque Converter
The torque converter in the 6T30 uses a single-plate lock-up clutch and features a “hyper-elliptical” oval cross-section shape. This design reduces the thickness of the torque converter, reducing the space it needs and keeping the overall width of the engine and transmission as narrow as possible for packaging advantages. The single-plate converter clutch uses GM’s electronically controlled capacity clutch (ECCC) technology to help reduce engine vibrations and ensure smooth operation.
IX Gear Pump
A compact on-axis, fixed-displacement IX gear-type fluid pump provides hydraulic pressure for shifting and lubrication. The pump features an IX gear (Drive/Driven) with a machined crescent in the pocket to reduce internal leakage and optimizes hydraulic efficiency. The inlet jet nozzle feature in the IX gear-type pump provides increased pump suction velocity, which helps optimize noise and vibration characteristics.
Ground And Honed Gears
To minimize gear noise, as well as vibration, the transmissions’ helical gears are ground and honed to ensure precise dimensions and tolerances. With closer tolerances, the gears are less prone to characteristic whining or humming, allowing the transmission to operate with exceptional quietness.
Unique Input Shaft Bushings
The input shaft requires no machining for grooves to contain fluid seals, which allows the shaft to retain maximum strength for its size and minimize cost.


Read more: http://gmauthority.com/blog/gm/gm-trans ... z3yu8Wc7LQ

Hope this helps

Derek
5 Door, 1.4 SE Automatic
Sovereign Silver
Intellilink 3.0


simon.billson.7
Posts: 4
Joined: Thu Aug 24, 2017 10:11 pm

Re: 6 speed automatic transmission

Post by simon.billson.7 » Sat Aug 26, 2017 12:12 am

Delboy_Lee wrote:This is information I have found on the Automatic Gear Box:

GM 6-Speed 6T30 MH9 Hydra-Matic Automatic Transmission:

The Hydra-Matic 6T30 (production code MH9) is a six-speed automatic transmission produced by General Motors for use in small front-wheel-drive vehicles with a transverse power train orientation. Developed in-house by General Motors, the Hydra-Matic 6T30 is part of the 6TXX family of transmissions that succeeded the 5TXX family. The 6T30 is the least robust unit in its family.

Six-speed automatic transmissions are integral to GM’s initiative to offer vehicles with excellent fuel economy. The Hydra-Matic 6T30 transmission delivers on that promise. It was designed for compact FWD applications and is part of GM’s family of technologically advanced, fuel-saving six-speed automatic transmissions. Shared traits between the 6TXX family – and other Hydra-Matic six-speeds is to reduce complexity, size and mass, including clutch-to-clutch operation that enables the six-speed to be packaged into approximately the same space as a four-speed automatic.
Because of the wide ratio spread, first gear is a very high ratio, which provides brisk acceleration from a stop. Sixth gear, however, is an overdrive ratio, which keeps the engine revolutions lower for highway cruising, reducing engine friction losses and optimizing fuel economy.
On-Axis Design
Instead of “folding” the transmission around the end of a transversely mounted engine, which has been one of the dominant GM transaxle design conventions, the 6T30 contains all of the gearing on the engine crankshaft centerline. The advantages of this layout enables a shorter overall vehicle length, more interior room and lower powertrain height.
Clutch-To-Clutch Shift Operation
Three planetary gearsets are used with three stationary clutches and two rotating clutches, which save space compared to freewheeling designs. Freewheeling mechanisms allow accurate timing between shifts, but also take up more space and add more components to the transmission. Through electronic controls, the clutch-to-clutch concept of the 6T30 delivers optimal shift timing.
Gear changes from second to sixth gear ratios are accomplished with a precise clutch-to-clutch action, where the clutch is engaged in one gear at exactly the same time it is released in another. The first-to-second upshift, however, is a freewheeling action, where the second gear clutch engages while the first gear one-way clutch spins freely. This allows a greater degree of smoothness at lower vehicle speeds.
Adaptive Shift Controls
Adaptive shift controls include automatic grade braking, which commands the transmission to remain in a lower gear if the vehicle is decelerating or coasting on a downgrade. This takes advantage of engine braking to prevent unwanted acceleration. This reduces the number of brake applies for the driver to brake during a hill descent. The control module receives input that monitors brake pedal usage, vehicle acceleration rate, throttle position, and even whether a trailer is connected to the vehicle.
Space-Saving Hyper-Elliptical Torque Converter
The torque converter in the 6T30 uses a single-plate lock-up clutch and features a “hyper-elliptical” oval cross-section shape. This design reduces the thickness of the torque converter, reducing the space it needs and keeping the overall width of the engine and transmission as narrow as possible for packaging advantages. The single-plate converter clutch uses GM’s electronically controlled capacity clutch (ECCC) technology to help reduce engine vibrations and ensure smooth operation.
IX Gear Pump
A compact on-axis, fixed-displacement IX gear-type fluid pump provides hydraulic pressure for shifting and lubrication. The pump features an IX gear (Drive/Driven) with a machined crescent in the pocket to reduce internal leakage and optimizes hydraulic efficiency. The inlet jet nozzle feature in the IX gear-type pump provides increased pump suction velocity, which helps optimize noise and vibration characteristics.
Ground And Honed Gears
To minimize gear noise, as well as vibration, the transmissions’ helical gears are ground and honed to ensure precise dimensions and tolerances. With closer tolerances, the gears are less prone to characteristic whining or humming, allowing the transmission to operate with exceptional quietness.
Unique Input Shaft Bushings
The input shaft requires no machining for grooves to contain fluid seals, which allows the shaft to retain maximum strength for its size and minimize cost.


Read more: http://gmauthority.com/blog/gm/gm-trans ... z3yu8Wc7LQ

Hope this helps

Derek
Yeah that's exactly what I have been looking for. Many thanks for taking the time to seek it out and post it. Simon.


Sent from my iPhone using Tapatalk


Susan44
Posts: 170
Joined: Tue Jan 05, 2016 12:33 pm

Re: 6 speed automatic transmission

Post by Susan44 » Sun Aug 27, 2017 8:35 am

Yes definitely a hydraulic torque converter as opposed to the awful easytronic and the similar dry option preferred by Fiesta "autos".
Couple that with the hill start feature and its one of the easiest small cars to drive.
Best auto box for small cars on the market IMO but they do have the first 3 gears on very low gearing for acceleration and if you use it in M mode you can't take your hand off the stick for the first 3 as the revs build up so quickly it redlines on full power (unlike the throttled manual maps). Stays in 6th for most of the time but drops into 5th at 70mph on hilly motorway stretches. Keeps the motor at about 2000 to 2500 rpm most ofthe time. Hence economy only about 37mpg average.

Auto 1.4 turbo would be a car to have but not sure that box would take the power.
1.4 Auto SE


simon.billson.7
Posts: 4
Joined: Thu Aug 24, 2017 10:11 pm

Re: 6 speed automatic transmission

Post by simon.billson.7 » Sat Nov 25, 2017 12:39 am

Susan44 wrote:Yes definitely a hydraulic torque converter as opposed to the awful easytronic and the similar dry option preferred by Fiesta "autos".
Couple that with the hill start feature and its one of the easiest small cars to drive.
Best auto box for small cars on the market IMO but they do have the first 3 gears on very low gearing for acceleration and if you use it in M mode you can't take your hand off the stick for the first 3 as the revs build up so quickly it redlines on full power (unlike the throttled manual maps). Stays in 6th for most of the time but drops into 5th at 70mph on hilly motorway stretches. Keeps the motor at about 2000 to 2500 rpm most ofthe time. Hence economy only about 37mpg average.

Auto 1.4 turbo would be a car to have but not sure that box would take the power.


Sent from my iPhone using Tapatalk


simon.billson.7
Posts: 4
Joined: Thu Aug 24, 2017 10:11 pm

Re: 6 speed automatic transmission

Post by simon.billson.7 » Sat Nov 25, 2017 12:54 am

Just noticed your very helpful description of the 6 speed auto box. Thanks. I’ve driven two of these cars now and yes, the gear change is very smooth and performance/economy is vastly improved over the previous 4 speed Unit. One strange thing about the new Unit on both 6 speed transmissions is that sometimes when either moving slowly in stop start traffic jams or following lengthy reversing manoeuvres (I’m a driving instructor) it can suffer what I can only describe as a clutch judder which quite violently shakes the whole car and feels as though it’s about to stall (although it never has). I’ve never experienced that in any torque converter auto before. I have however noticed it quite a lot on those horrible easytronic transmissions. It seems a little odd but hopefully not an indication of trouble brewing....


Sent from my iPhone using Tapatalk


User avatar
FirestoneDK
Posts: 204
Joined: Wed Sep 16, 2015 7:21 pm
Location: Roskilde, Denmark

Re: 6 speed automatic transmission

Post by FirestoneDK » Sat Nov 25, 2017 9:07 am

Susan44 wrote:
Sun Aug 27, 2017 8:35 am
Auto 1.4 turbo would be a car to have but not sure that box would take the power.
The 6T30 is only rated for 175 newtonmeters so it's a no go. But they do make other auto boxes that are rated higher.
http://www.opel-infos.de/getriebe/6t.html It's in german, but describes alot technical details about the 6TXX boxes.


Susan44
Posts: 170
Joined: Tue Jan 05, 2016 12:33 pm

Re: 6 speed automatic transmission

Post by Susan44 » Sat Nov 25, 2017 4:17 pm

simon.billson.7 wrote:
Sat Nov 25, 2017 12:54 am
......One strange thing about the new Unit on both 6 speed transmissions is that sometimes when either moving slowly in stop start traffic jams or following lengthy reversing manoeuvres (I’m a driving instructor) it can suffer what I can only describe as a clutch judder which quite violently shakes the whole car and feels as though it’s about to stall ....


Sent from my iPhone using Tapatalk
Ah not just me then! Yes mine does that occasionally usually when the car is moving in slow traffic under tickover gas being slowed by a light foot brake . You need to let the foot brake off if you have room in front of you, or if not push the lever into N. Not easy to explain to a learner, probably illegal, and should not be necessary. Probably happened to me half a dozen times in 2 years. Typical ECU brain fart for this model, along with randomly flattening the battery overnight and random radio blasts when you open the doors.

As a pro driver they may take notice of you where they will ignore a silly old woman.
1.4 Auto SE


Rob111gb
Posts: 2
Joined: Sat Aug 19, 2017 9:41 pm

Re: 6 speed automatic transmission

Post by Rob111gb » Sat Dec 02, 2017 11:43 pm

Im also a driving instructor teaching with the auto box. I’ve never had a problem with shuddering when reversing, only when going or sneaking forward it shudders. I had an ‘05’ Astra that had the same feeling when clutch plates were hot during stop start traffic.
It is strange though, pupils always think they’ve stalled when it happens.


Post Reply

Return to “Faults & Technical”


Who is online

Users browsing this forum: Google Adsense [Bot] and 2 guests