ZB Commodore 8sp VS 9sp.

[GTOPB]

Greetings lads,
To get straight to the point, I am now looking to buy a new car and I am very strict with gearbox reliability. This is mainly because I drive an Audi A5 Coupe with the 7 speed dct and it had my wallet bankrupt a few times.
As you may all know, ZBs are released with 2 different transmissions. The 8sp from Aisin on diesel and the 9sp from GM on the petrol. I was surprised to see how reviews from domestic drivers are the exact opposite from the none Aussie drivers. There are numerous articles on how the GM 9sp was not meant to be for the v6 AWD models because it cannot handle the 400nm torque from the 2lt turbo diesel engine. So 400nm is not okay but 381nm from the v6 is okay? Hmm, other article also says that the 9speed was rejected by Ford to be used and many more articles that says the 8sp is the superior. I am not too sure on this but it seems like V6 ZB Commodores are sold with a different transmission in other countries, under a different name such as Buick Regal or Insignia.

I plan to get a V6 zb commodore, VXR trim most likely. I look forward to hearing feedbacks from other ZB Commodore owners on gearbox reliability or dynamic aspect of it, or anything really that I should know. Should I really be that concerned?

BTW, as far as I know ZB commodore v6 LGX engine is shared to the v6 Chevy Camaro, (although with a different gearbox) and it seems like they have plenty of mods for this engine. I know we cannot expect the same here in Australia but i barely see any performance mods the ZB. Is that mainly because of the 9sp gearbox in V6s? or simply low in demand?

 

[Jack GS]

I cannot speak to ZB ownership directly, as 1) I don't own one and 2) I believe the GM Australia team tuned the ZBs to suit your specific market. The powertrains may act noticeably different between each market. We don't even have a diesel option in the US... That being said, I can shed some light on most of the topics you brought up. I apologize in advance for my long winded response. TL;DR at the end.

8-speed (Aisin AF50-8)

The Aisin 8-speed was the first transverse 8-speed built and implemented. It has had the advantage of time for both development and reliability. That being said, it's not perfect. Most Regal owners with the 8-speed are quite displeased with its responsiveness when driving aggressively. It is slow to downshift, lugs the engine instead of downshifting, and is described as being dim-witted overall. The Trifecta tune seems to eliminate these complaints.​

​

If only cruising around, and not getting on the throttle at every given opportunity, it's just fine. I have driven a family member's 2.0T AWD Regal with the 8-speed on numerous occasions. Since Australia and NZ don't get that particular trim, it's not the best comparison but it's my only experience with the 8-speed. While it is less responsive than the 9-speed, it is still quite smooth.​

​

Max torque values are 480 N⋅m (350 lb⋅ft)​

​

9-speed (GM 9T50 or 9T60)

GM and Ford did co-develop transmissions. GM developed the 9-speed while Ford developed a 10-speed. All said and done, the 9-speed was heavier, more expensive, and only 1 mpg more efficient than the trans it replaced in the Buick Envision. Ford opted to forgo the extra gear and weight, not because the 8-speed was superior, but because it went against their weight and economy goals. Ford actually made an 8-speed out of the GM 9-speed for certain applications.​

​

I think Ford missed the point. While it may not seem like much of an improvement on paper, the 9-speed shifts like butter and never hunts for gears. GM argued that is has a more premium feel, something other 8 and 9-speeds lack. It is very responsive and when put into GS mode, it's amazing. I have had no complaints about the 9-speed in my Regal GS. While I understand Ford's choice, I'm gonna side with GM on this one (take my bias into account).​

​

The 9T50 is mostly used for the 2.0T (LTG etc.) and made its way into almost every GM vehicle with a four banger. The 9T60 was introduced to handle the 3.6 V6 (LGX etc.) and wound up in the LaCrosse, Envision, and Regal GS. There is also a 9T65 that's exclusive to the larger GM SUVs using the same HFV6 family of engines.​

​

I couldn't find official max torque values...​

Reliability

The Aisin 8-speed has been around a little longer. In use since 2013, GM is not the only company using the Aisin unit. To name a few... Lexus, Toyota, Volvo, BMW, MINI, and VW are using some variant of it to this day. It certainly has a longer history and better pedigree.​

​

It's kinda too early to make a call on the 9-speed just yet, but overall it's been a performer. Since implementation of the 9-speed in 2017, there have been no major, or minor, issues. It is far superior to the problem riddled ZF 9-speeds. The GM 9-speed is well-like and is on its way to being just as highly regarded as the Aisin unit.​

Aftermarket Support

If you plan on cranking up the power and torque figures, the LTG is currently the better option. There are far more vehicles with the LTG and therefore, there is more support for them. With a tune and some bolt-ons, the LTG quickly reaches (and exceeds) the output of the stock LGX.​

​

The lack of support for the LGX stems from the low demand, as you've stated. There's simply not a large enough customer base asking for transverse V6 performance mods. Tunes are available, but with a naturally aspirated engine, the gains are underwhelming. I elaborate on the supercharger situation HERE.​

​

TL;DR

The 9-speed is fantastic out of the box. The 8-speed is not quite as sporty or intelligent as the 9-speed, but can be remedied with a tune. Reliability is great for both and unless you intend to go crazy with performance mods, they should both hold up. I'd go with the 9-speed and then decide between the LTG or LGX. The GKN Twinster AWD system alone is enough to go the V6 route.​

​

P.S. I can attach links if desired, but most of this info is readily available with a simple Google search.​

 

[87VLCALAIS]

I'd second what Jack GS said.

I have the RSV and the 9 speed auto in my opinion is pretty damn good. One feature I like is that it will change down as you decelerate meaning it is already in the right gear when you need to accelerate.

You'll love the VXR. It was out of my price range but the adjustable suspension and the Matix LED headlights are very good.

 

[GTOPB]

I cannot speak to ZB ownership directly, as 1) I don't own one and 2) I believe the GM Australia team tuned the ZBs to suit your specific market. The powertrains may act noticeably different between each market. We don't even have a diesel option in the US... That being said, I can shed some light on most of the topics you brought up. I apologize in advance for my long winded response. TL;DR at the end.

8-speed (Aisin AF50-8)

The Aisin 8-speed was the first transverse 8-speed built and implemented. It has had the advantage of time for both development and reliability. That being said, it's not perfect. Most Regal owners with the 8-speed are quite displeased with its responsiveness when driving aggressively. It is slow to downshift, lugs the engine instead of downshifting, and is described as being dim-witted overall. The Trifecta tune seems to eliminate these complaints.​

​

If only cruising around, and not getting on the throttle at every given opportunity, it's just fine. I have driven a family member's 2.0T AWD Regal with the 8-speed on numerous occasions. Since Australia and NZ don't get that particular trim, it's not the best comparison but it's my only experience with the 8-speed. While it is less responsive than the 9-speed, it is still quite smooth.​

​

Max torque values are 480 N⋅m (350 lb⋅ft)​

​

9-speed (GM 9T50 or 9T60)

GM and Ford did co-develop transmissions. GM developed the 9-speed while Ford developed a 10-speed. All said and done, the 9-speed was heavier, more expensive, and only 1 mpg more efficient than the trans it replaced in the Buick Envision. Ford opted to forgo the extra gear and weight, not because the 8-speed was superior, but because it went against their weight and economy goals. Ford actually made an 8-speed out of the GM 9-speed for certain applications.​

​

I think Ford missed the point. While it may not seem like much of an improvement on paper, the 9-speed shifts like butter and never hunts for gears. GM argued that is has a more premium feel, something other 8 and 9-speeds lack. It is very responsive and when put into GS mode, it's amazing. I have had no complaints about the 9-speed in my Regal GS. While I understand Ford's choice, I'm gonna side with GM on this one (take my bias into account).​

​

The 9T50 is mostly used for the 2.0T (LTG etc.) and made its way into almost every GM vehicle with a four banger. The 9T60 was introduced to handle the 3.6 V6 (LGX etc.) and wound up in the LaCrosse, Envision, and Regal GS. There is also a 9T65 that's exclusive to the larger GM SUVs using the same HFV6 family of engines.​

​

I couldn't find official max torque values...​

Reliability

The Aisin 8-speed has been around a little longer. In use since 2013, GM is not the only company using the Aisin unit. To name a few... Lexus, Toyota, Volvo, BMW, MINI, and VW are using some variant of it to this day. It certainly has a longer history and better pedigree.​

​

It's kinda too early to make a call on the 9-speed just yet, but overall it's been a performer. Since implementation of the 9-speed in 2017, there have been no major, or minor, issues. It is far superior to the problem riddled ZF 9-speeds. The GM 9-speed is well-like and is on its way to being just as highly regarded as the Aisin unit.​

Aftermarket Support

If you plan on cranking up the power and torque figures, the LTG is currently the better option. There are far more vehicles with the LTG and therefore, there is more support for them. With a tune and some bolt-ons, the LTG quickly reaches (and exceeds) the output of the stock LGX.​

​

The lack of support for the LGX stems from the low demand, as you've stated. There's simply not a large enough customer base asking for transverse V6 performance mods. Tunes are available, but with a naturally aspirated engine, the gains are underwhelming. I elaborate on the supercharger situation HERE.​

​

TL;DR

The 9-speed is fantastic out of the box. The 8-speed is not quite as sporty or intelligent as the 9-speed, but can be remedied with a tune. Reliability is great for both and unless you intend to go crazy with performance mods, they should both hold up. I'd go with the 9-speed and then decide between the LTG or LGX. The GKN Twinster AWD system alone is enough to go the V6 route.​

​

P.S. I can attach links if desired, but most of this info is readily available with a simple Google search.​

Wow Thank you so much. I would have went to Harvard if you were my teacher 10yrs ago hahahha.

I'm very open to the 2.0turbo option especially because I know it's a lot of fun.
My car is fitted with the same size engine with similar power. The only reason why I considered VXR was because of the AWD system. I'm a quattro fan so awd much more preferred than fwd. And if I am getting one, might as well just get it in full leather seats.

In regards to your 8sp vs 9sp comparison, I guess it's plausible to say that 9sp worth giving a go. Gearbox seems smart and zappy so im pretty excited to see how it is compared to dual clutches. That brings me to my last concern. On the ZB forum, you can find two extreme examples of the 9sp in practice. Ones who says they r satisfied and the ones who had their gearbox replaced due to some metal particles created from inside that ruins the gearbox.
Regardless to which model I'll get, I'm only looking out for those that are under 20k on odo with 2~3YRS remaining warranty. My budget is 45k. If the tranny was to fail during the early stage of its life, I dont know if it will fail before or after the warranty period cuz I drive less than 10k a year. Oh well, I know buying a car is a gamble, new or used, but thank you for your reply.

 

[Anthony121]

The 2.0 lt and 9 Speed was good for doing the following. I think the V6 did the same. At 40kms/h, floor it then let go and then floor it again within a sec.

 

[stooge]

i thrash my v6 with the 9 speed and the only time i have ever had an issue with it is while doing 100 on cruise control going up hill if i dump it to overtake it will drop a few gears and goto 6000rpm and hold it until i cancel cruise control.
apart from that it is pretty sweet

 

[GTOPB]

i thrash my v6 with the 9 speed and the only time i have ever had an issue with it is while doing 100 on cruise control going up hill if i dump it to overtake it will drop a few gears and goto 6000rpm and hold it until i cancel cruise control.
apart from that it is pretty sweet

Just a quick question. Although I can't speak for all dual clutch trannys, the one that is fitter into my A5 is very responsive. Responsive as in, immediate shifts in manual mode. Whenever I use the paddle shifters or the up and down on the gear knob, it shifts the way you expect to and hold gears during close to max rpm for some time too. Where as my other car lexus is250 feels like it has glue instead of tranny fluids. Slow shifts and it doesn't follow ur shifts either on paddles and knob + -. I know dct r lot faster but not downshifting or upshifitng when u want isnt speed issue..

When you put it in manual mode, do u find the 9sp responsive and does it shift accordingly to your shifts?

 

[stooge]

When you put it in manual mode, do u find the 9sp responsive and does it shift accordingly to your shifts?

i have never used it in manual mode, i used to use my vf ssv in manual mode a fair bit and found it a bit sluggish on the change but i have never felt the need to use the zb in manual mode because it just works.

i guess i should try it one day and see if it is any good.

 

[Jack GS]

When you put it in manual mode, do u find the 9sp responsive and does it shift accordingly to your shifts?

I think that's an unfair comparison lol. No other trans in a street car is gonna be as responsive as a DCT, the GM 9-speed included. In manual mode, it responds fairly quickly but it's not seemless enough to go unnoticed. There's still discernable lag if you're being critical.

I never feel the need to intervene though. The 9-speed holds gears and keeps the engine in higher revs all on its own. It manages those 9 gears better than I could manually. It's hard to explain but it just works.

 

[Badgerdog]

I find the 9 speed to be a very good transmission. The vast majority of the time the gear changes are super smooth and imperceptible.
Its very intuitive and almost always feels like its in the right gear for the task at hand. That said, it can't see ahead so sometimes I clip it down a gear on the paddle shifters at the bottom of a hill. Some info on the development of the 9 speed https://www.wardsauto.com/technology/new-9-speed-pushes-tech-limit-gm-says

One little known fact is you can slide the gearstick across and put it into sport manual mode wherein it will hold gears indefinitely until you instruct it otherwise with the paddle shifters. I've very rarely done this but it can be a bit of fun on a twisty back country road if you want to keep the revs up and get even more thrust out of the corners.

An especially likeable factor of the 9 speed is its smoothness even when stone cold, many gearbox's are not especially super buttery smooth from the get go. The only gearbox I've ever used that's slightly better is the world renowned ZF8 speed in a BMW with their expert software calibration, (the same gearbox in a Chrysler SRT8, (albeit manufactured in the U.S) was significantly inferior without the best TCM programming).

In terms of the aisin 8 speed my only experience was in a Lexus and I was underwhelmed. Its considerably inferior to GM's 9 speed in my opinion.
Likewise the in house developed 8 speed in use by Kia in their Stinger wherein I noted gear changes not nearly as smooth, and considerably more dull witted and less intuitive than the GM 9 speed.

Its not an exaggeration for GM to claim their 9 speed has a premium feel because it does. In my opinion its very, very nearly as good as the world renowned ZF 8 speed in use by many luxury European vehicle manufacturers.

There's always a fly in the ointment though...because all that said it does appear they are having some issues with the 65 version of this gearbox, (thankfully we get the 60 version in our V6 vehicles)
GM Addressing 9T65 9-Speed Transmission Issues | GM Authority