GM's new 9 speed 9T50

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Ward's article on the 9T50.

Quote:
“We don’t see the benefit of going higher than 10 forward speeds,” Meagher tells WardsAuto following a presentation on the technologies here.

But never say never, he adds, noting that when GM deployed its revolutionary lineup of 6-speed automatic transmissions a decade ago no one imagined hardware and software technology would advance so dramatically to permit 9- and 10-speed executions.

“So you never really know for sure,” he admits.


Quote:
The new 9-speed yielded GM 60 new patents and required 800 prototypes. It is the same size as the old 6-speed and weighs about 22 lbs. (10 kg) more. The most unique element of the unit is an industry-first deployment of a selectable 1-way clutch, which can hold torque or operate freely depending on the situation.


Quote:
The unit is filled with Castrol-brand DEXRON-VI fluid to eliminate service changes under normal driving conditions. GM says the fluid features consistent viscosity, consistent shift performance and reduced degradation.


Quote:
In-house logics software inside a 32-bit transmission control module handles all shift events for smooth, precise ratio changes, GM says. It also monitors transmission performance and compensates for wear in parts such as the clutch plate to maintain consistent performance over time.


Quote:
The controller is mounted outside the gearbox to reduce packaging and manufacturing complexity, and it pulls vehicle-specific calibration from the cloud to be added to the core program as the car or truck exits the assembly line. It also enables manual shift control and grade logic, GM says.


Quote:
The 9T50 features a wider 7.6:1 overall ratio, compared with 6.0:1 in its 6-speed predecessor, a deep 4.69 first gear for off-the-line performance and a tall 0.62 top gear for fuel-efficient, low-rpm highway cruising and optimal NVH.

Sixth gear is equivalent to eighth gear on the new transmission, too, so compared with the 6-speed the 9-speed offers two fuel-saving overdrive gears. Seventh gear is the direct-drive gear, while ninth gear is in use up to 52% of the time.
 
Lets see if they have problems once they're in use for a year or so. The ZF9 speed was supposed to be great, and the early adapters learned otherwise. Maybe GM got this one right.
27.gif
 
GM routinely does well with their in house designs. Their transmission expertise is very high, I love my 6 speed HD trans in our service vans. The current 8 speed units have mostly satisfied owners, expect good things for this one...
 
The 6 speed in our Malibu is awesome.

The 4 speed in my Impala does whatever it wants. Feels like it's on the verge of complete failure one day, and excellent the next.
 
I hope so.. The ZF was a pile of garbage, I test drove a Chrysler 200 with the pentastar 3.6 because I liked that engine... The driving experience sucked because the 1-2 shift and 2-3 shift was always rough and unacceptable on a car with only 20k.

Also not necessarily the transmission itself but the programming was terrible too. If you were trying to increase the speed of the car at anything more then a super lazy pace, it would either sit there and do nothing at like 1500 RPM or it would drop like 4 or 5 gears and jump to about 5 grand. NO middle ground.

I had a 09 Malibu 3.6 with the 6 speed and it drove pretty good (shifted much better with 89 octane) but those were plagued by the 3, 5, R wave plate issue to the point GM extended the warranty on the transmission to 120,000... My waveplate failed at 124,000. GM did cut me a small break that saved me $700 but I still paid $2600 out of pocket for the tear down and wave plate fix. Once I got it back it never did hit 3rd gear quite right, so I dumped it and seeked out a car with a manual. I am automatic transmission free and it's nice!! haha
 
Last edited:
Originally Posted By: Tman220
I hope so.. The ZF was a pile of garbage, I test drove a Chrysler 200 with the pentastar 3.6 because I liked that engine... The driving experience sucked because the 1-2 shift and 2-3 shift was always rough and unacceptable on a car with only 20k.

Also not necessarily the transmission itself but the programming was terrible too. If you were trying to increase the speed of the car at anything more then a super lazy pace, it would either sit there and do nothing at like 1500 RPM or it would drop like 4 or 5 gears and jump to like 5 grand. NO middle ground.


That was my opinion of the 9 speed ZF bolted to the Pentastar. The transmission sucked.
 
Originally Posted By: SteveSRT8
GM routinely does well with their in house designs. Their transmission expertise is very high, I love my 6 speed HD trans in our service vans. The current 8 speed units have mostly satisfied owners, expect good things for this one...


I thought their transmission expertise was high as well, but not the case on my 2016 Sierra. That trans in a major POS and clangs, bangs and hard shifts all the time.

Love the truck, Hate the trans. The 8L90E trans has terrible programming, with no fixes available from GM (been to dealer several times).

I have owned several GM trucks over the years (both new and used). This trans is the most harshest shifting/rough shifting transmission I have ever had.
 
IMO it takes a couple/few years to iron out the bugs. Reading message boards and talking with owners, techs, and other enthusiasts seems to back that up. I'd wait.
 
Is the ZF a pile of junk hardware wise, or is its programming in these applications lame ?

Bad code can hobble the best transmissions.

UD
 
Last edited:
Originally Posted By: UncleDave
Is the ZF a pile of junk hardware wise, or is its programming in these applications lame ?

Bad code can hobble the best transmissions.

UD


I heard mostly software, along with some hardware issues. I'm not sure if they've found a fix though.
 
I thought the ZF's were great units? Or am I confusing the various ones? Probably confusing the 8&9 speed units; I know the 6 is the FWD one (Caravan, probably others).
 
Originally Posted By: UncleDave
Is the ZF a pile of junk hardware wise, or is its programming in these applications lame ?

Bad code can hobble the best transmissions.

UD


Early ZF 9 spd has a snap ring issue and obviously software issues but the hardware was corrected mid 2015 and the software has been improved, drove a friends Cherokee with the 3.6 and 9spd and it hauls arse and shifts great.

Liek anything else the bugs get worked out, Honda is now going thru the leanring curve on their ZF 9spds in the Acuras.

I have the 8HP70 in my hemi WK2 and it is the best transmision I have driven. makes all the old 5 and 6 spds useless.
shifts much better, always in the correct gear and when in sport mode will hold the shift points
smile.gif
Plus getting 22 mpg on highway isnt bad either!
 
Originally Posted By: daddi
Originally Posted By: SteveSRT8
GM routinely does well with their in house designs. Their transmission expertise is very high, I love my 6 speed HD trans in our service vans. The current 8 speed units have mostly satisfied owners, expect good things for this one...


I thought their transmission expertise was high as well, but not the case on my 2016 Sierra. That trans in a major POS and clangs, bangs and hard shifts all the time.

Love the truck, Hate the trans. The 8L90E trans has terrible programming, with no fixes available from GM (been to dealer several times).

I have owned several GM trucks over the years (both new and used). This trans is the most harshest shifting/rough shifting transmission I have ever had.


We own Silverados but have no 8 speeds in our lot. The 6 speed in the 1500 models is COMPLETELY different from the 3500 HD models. It is primarily bad programming IMO, as the 6L90/6L80 is a great unit for us both in durability and driving experience.

They could all learn a lesson from the 8 speed ZF boxes. My friend's new BMW turbo'd 4 banger with one is fantastic, extremely smooth but super responsive.

It's the same way in my Wife's RAM. The 5.7/8 speed combo is one of the best transmissions I have ever had the pleasure of owning.

Yet I know folks here who have criticized the 8 speed in the 300's with the V6, seems to me the programming is the primary fault here...
 
Last edited:
Originally Posted By: daddi
I thought their transmission expertise was high as well, but not the case on my 2016 Sierra. That trans in a major POS and clangs, bangs and hard shifts all the time.

Love the truck, Hate the trans. The 8L90E trans has terrible programming, with no fixes available from GM (been to dealer several times).

I have owned several GM trucks over the years (both new and used). This trans is the most harshest shifting/rough shifting transmission I have ever had.


Maybe there's a reprogram available for it that the dealer isn't aware of. Since your truck is so new it may take a year or so for the update to become available. Let's hope one comes out and it will solve those issues. In the meantime you can always complain about it to corporate and see if they do anything about it. If you complain to the dealer chances are corporate won't hear about it.
 
Quote:
“We don’t see the benefit of going higher than 10 forward speeds,” Meagher tells WardsAuto following a presentation on the technologies here.

But never say never, he adds, noting that when GM deployed its revolutionary lineup of 6-speed automatic transmissions a decade ago no one imagined hardware and software technology would advance so dramatically to permit 9- and 10-speed executions.

“So you never really know for sure,” he admits.


Translation: "We made some nice money on our complicated garbage so we are going to do more messing with what already worked."

Quote:
The new 9-speed yielded GM 60 new patents and required 800 prototypes. It is the same size as the old 6-speed and weighs about 22 lbs. (10 kg) more. The most unique element of the unit is an industry-first deployment of a selectable 1-way clutch, which can hold torque or operate freely depending on the situation.


Translation: " You'll enjoy the cookies and upselling in our nice dealership as you await the TSB update of the logic that is messed up after owning the vehicle a year. Don't worry, Ricky has the Ozzy Playing and does a gudenough job"

Quote:
The unit is filled with Castrol-brand DEXRON-VI fluid to eliminate service changes under normal driving conditions. GM says the fluid features consistent viscosity, consistent shift performance and reduced degradation.


Translation: "We spoke with Toyota about their brilliant dipstick-less method in which you need a vacuum supplycombined with electronic temp information combined with the overflow plug procedure..... wait.....nah.....just burn that baby up!"

Quote:
In-house logics software inside a 32-bit transmission control module handles all shift events for smooth, precise ratio changes, GM says. It also monitors transmission performance and compensates for wear in parts such as the clutch plate to maintain consistent performance over time.


Translation: "We found a new way to give you a transient 'shift quality code' that you can't reproduce at the dealer because the car is too warm by the time you drive it there"

Quote:
The controller is mounted outside the gearbox to reduce packaging and manufacturing complexity, and it pulls vehicle-specific calibration from the cloud to be added to the core program as the car or truck exits the assembly line. It also enables manual shift control and grade logic, GM says.


Translation: We can deny you warranty work because we know if you waited the appropriate amount of time to shift from reverse to drive backing out of WalMart. Oh, and it now will be affected by road salt."

Quote:
The 9T50 features a wider 7.6:1 overall ratio, compared with 6.0:1 in its 6-speed predecessor, a deep 4.69 first gear for off-the-line performance and a tall 0.62 top gear for fuel-efficient, low-rpm highway cruising and optimal NVH.

Translation: "This baby will limp into the tallest gear possible and shudder till the cows come home."

Sixth gear is equivalent to eighth gear on the new transmission, too, so compared with the 6-speed the 9-speed offers two fuel-saving overdrive gears. Seventh gear is the direct-drive gear, while ninth gear is in use up to 52% of the time.


Translation: "Shudder baby Shudder... tech report "normal characteristics"
 
Originally Posted By: SteveSRT8


Yet I know folks here who have criticized the 8 speed in the 300's with the V6, seems to me the programming is the primary fault here...


I think the issue is the 8 speed in the V6 vehicles is not the same 8 speed that's used with the diesel, or Hemi Chrysler products. The HD unit is much better.
 
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