Engineering Explained explains why the ZF8HP 8 Speed transmission is class leading

motex · 05-05-2019, 01:29 AM

Quote:

Originally Posted by Red Bread

Quote:

Originally Posted by Viffermike

Red Bread nailed it: Programming variety is one the ZF8's two biggest strengths. The other? Modular, scalable build specs. The ZF8's also used in Dodge/Ram trucks and Rolls-Royces, fer cryin' out loud.

It changed the transmission game nearly as much as the DCT in general itself -- and has as much to do with the impending death of the manual as the DCT does, too.

You can pull my manual from my cold, dead...

While that's true, our Q5 has a 7s DCT that I fail to see any advantages over the ZF8. I assume Audi just has a warehouse full of the things and is burning off supply and will eventually change over to the ZF8.

My wife has a brand new 2019 Q5 with a 7 speed DCT, coming from a 2015 Q5 with probably one of the worst automatic transmissions I have driven, when buying the new Q5 I have had high expectations about the 7s DCT, but for my surprise another failure, rough in low speeds, doesn't change when you want, it makes stupid changes when cold, etc etc.
So probably you are right, they're burning inventory of DCT's

CntryClub007 · 05-06-2019, 12:19 AM

Quote:

Originally Posted by SleepingBMW

Quote:

Originally Posted by EstorilM240

Quote:

2. BMWs SMG broke a lot but it is still the fastest shift time they have sold and with a modern cpu attached and a reliable pump it would be the best performance transmission. It wouldn't be the smoothest but I'm assuming we are here because we want performance. Hydraulic pump and dog clutch sequentials are still the transmission of Porsche BMW and every other race car. 20 years of development to improve SMGs for street use would have been expensive and have limited application (M cars) but it would be much better than ZF8.

I might be missing something, but unless you're talking about the race-prepared, straight-cut teeth transmissions, the DCT is faster than the BMW SMG's that were used on the E36 and E46 M3 (single clutch automated transmissions) in shifting. They both have two clutches and helical gears.

The BMW SMG I/BMWSMG II/Audi R Tronic/Lamborghini e gear etc. transmissions all have shift times in the 150-300ms range and are basically dead because they're painfully jerky and slower than dual clutches, although they perhaps enjoyed a heyday in the late 1990s-2007 period before DSG/DCT came around. The Lamborghini Aventador is probably the last production car to have one, after the smart fortwo finally got a dual clutch.

Although jerky shifts feel more "real", it doesn't necessarily mean faster performance. I drive three pedal manual but would not put the ZF 8 into the "soulless mass produced commuter transmission", simply because the shift speeds are so good, even if it is super smooth. Then again, I contrast with ancient 3/4 speed autos and how 1-second long downshift reaction times would be sold as "tiptronic". I agree with chassis on the "in house not always better" - mainly based on Mercedes experiences as well, although with the 2-year-older 7G-Tronic, which was significantly slower and jerkier than I hoped for such a modern car. Also, Porsche somehow managed to acquire a 5G-Tronic on the 911 for a while, so BMW could license out one of the exotic transmissions if they really wanted.

You can watch videos of the smart fortwo 0-60 single-clutch automated manual, it's comical how long the shifts are.

If there's one single transmission that killed the stick shift, it is indeed the ZF8. You now need to sacrifice 2-3MPG's and 0.2s usually in the 0-60.

One anomaly I've found is, if the 7DCTs are so good, why do they still get 1 MPG worse than the 6MT on the EPA tests? M2 DCT is worse MPG, M4 DCT is worse MPG, so weird.

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True, though BMW doesn't have access to them, the fact they won't do what those other sports car companies did and develop a DCT for modern cars really tells you all you need to know about How bmws execs see the brand over the next five years.

I'd want to see the am division spin off to compete more with Porsche and Ferrari but BMW sees it as slap a few edgey design elements, a tune, and a price hike for printing money.

Happily for shareholders and unfortunately for sports car enthusiasts, companies all exist to eventually produce profits and results for their shareholders. When the halo effect and branding power of subsidizing your low-volume sports cars with your high-margin SUVs pays off in higher SUV sales, then you do it. When siphoning off some of those profits to R&D a slightly more technologically advanced cargo box in the X5 trunk or better air suspension or 360-degree cameras for the large vehicles is more worth it, executives will direct the money there.

BMW only makes about ~$5k profit per vehicle, Porsche makes $15K and has all of VW AG to share tech with, so there is less wiggle for BMW. Even so, the vast majority of Porsche profit is purely due to the badge and selling boatloads of Cayennes and Macans.

I'm not sure what the exact R&D cost of a new DCT would be, but the volume of DCT usage is surprisingly quite low for BMW. Making it work everywhere is not even that worth it to Audi with all their parts sharing sometimes, as they stick the S5 and RS5 with the ZF 8 as well since it accelerates just as nicely and they didn't have any R Tronic/DCT that fit the torque requirements, and works in the monstrously powerful Hellcats too. I wonder if there's a fundamental mechanical trade off in that a torque converter is a force multiplier while a clutch is fundamentally a torque divider, that gives torque-converter autos an advantage on takeoff or in shifts.

I'm also still a little surprised that it's so hard to just program a DCT to be ultra-smooth (can't you just rev match perfectly? There is already some DBW delay anyway), but what do you know.

SMGIII shifted in 65 ms with traction control off and in the highest setting and that's about 100ms faster than the last official PDK numbers. Especially if PDK is set up to shift the wrong way. Not to mention shifting two gears in a row etc etc.

That said SMG isn't smooth ever. PDK can be.
Porsche doesn't bother with PDK in its race cars either btw. They use sequentials to save weight and shift fast.

SMGs main weakness was the slow computer paired to it. A modern DCT will process the shift much faster even if the shift itself is slower than the SMG

So I've been on a journey the last few days...I went and test drove a V10 E60 M5 with SMG, and coming from a POS 320i with 2TB (Sport Auto Trans) coding, I couldn't have been any more disappointed in the M5. I know, this sounds weird, a V10? Yes. The car I loved since I was 15, I no longer love.

The M5 was like driving an Abrams tank. I could feel everything on the road (in a good way), suspension was superb (nice and stiff), steering was tight, brakes were spot on. Car was absolutely immaculate inside and out with 40K on the odometer. Ultimately, it was heavy with a feel of minimal agility.

However, the car just wouldn't "go", I literally asked the driver, this is fully mashed? He's like ya, fast, right? No. I needed to get behind the wheel. So I did, and it was just mediocre at best, it really was. I don't mean this in any rude, insulting way whatsoever to anyone who owns one, but I was just turned off by it all. The engineer in me loves the concept of the SMG and how it works, why it works etc...but it just seems dead with this other technology amongst us now.

Then, I began researching more about the V10, naturally aspirated vs. turbo vehicles, why power comes in at different times, and it really occurred to me that with a boosted motor, the vehicle behaves differently. Coupled to the correct transmission, makes for a pleasant combined and complementary experience.

I can obviously "rip" through the gears with the ZF and launch control in my POS 320i, the SMG was just constant whiplash back and forth on every gear change, I screwed with all of the DriveLogic settings, adjusted my driving style to nail the shifts, the shifting was insanely slow! Granted, I need to read into your entire post, but from what I can gather, it seems like these old school trans are just dead?

So what's the point of my post, not completely sure, HOWEVER, I ended up picking out a 340i, and I pick that up tomorrow, massively stoked to be stepping up in the rankings, so I guess that is cool.

brad850csi · 05-06-2019, 02:23 AM

Quote:

Originally Posted by CntryClub007

So I've been on a journey the last few days...I went and test drove a V10 E60 M5 with SMG, and coming from a POS 320i with 2TB (Sport Auto Trans) coding, I couldn't have been any more disappointed in the M5. I know, this sounds weird, a V10? Yes. The car I loved since I was 15, I no longer love.

The M5 was like driving an Abrams tank. I could feel everything on the road (in a good way), suspension was superb (nice and stiff), steering was tight, brakes were spot on. Car was absolutely immaculate inside and out with 40K on the odometer. Ultimately, it was heavy with a feel of minimal agility.

However, the car just wouldn't "go", I literally asked the driver, this is fully mashed? He's like ya, fast, right? No. I needed to get behind the wheel. So I did, and it was just mediocre at best, it really was. I don't mean this in any rude, insulting way whatsoever to anyone who owns one, but I was just turned off by it all. The engineer in me loves the concept of the SMG and how it works, why it works etc...but it just seems dead with this other technology amongst us now.

Then, I began researching more about the V10, naturally aspirated vs. turbo vehicles, why power comes in at different times, and it really occurred to me that with a boosted motor, the vehicle behaves differently. Coupled to the correct transmission, makes for a pleasant combined and complementary experience.

I can obviously "rip" through the gears with the ZF and launch control in my POS 320i, the SMG was just constant whiplash back and forth on every gear change, I screwed with all of the DriveLogic settings, adjusted my driving style to nail the shifts, the shifting was insanely slow! Granted, I need to read into your entire post, but from what I can gather, it seems like these old school trans are just dead?

So what's the point of my post, not completely sure, HOWEVER, I ended up picking out a 340i, and I pick that up tomorrow, massively stoked to be stepping up in the rankings, so I guess that is cool.

Yeah the SMG is a bucket of crap. I would have been keen for an E61 M5 but I drove 4 different E60 and E63s and I just couldn't deal with the gearbox.

The dual clutch in the F series M5 and M6 is wonderful though. Go for a drive in one

///Mvious · 05-06-2019, 02:59 AM

The way BMW adapts the ZF8 makes it far better than ANY other auto trans. PDK excluded. ZF8 it’s the best auto on the road and the way BMW tunes it to perform is by far the best all around in terms of shift quality/performance and how well it behaves in automatic mode. It downshifts EXACTLY when you ask it to, and hold revs very well given the driving mode you enagage. I’ve driven everything from new Mercs/AMGS, Jags, range rovers , Audi, Alfa’s and New X5/X7/ X3M. I’d have searched for a competitor to bmws ZF8s and nothing comes close. The way BMW tunes it is far superior to others on the road and it’s clear if you switch from a BMW ZF8 to another ZF8.

mbanck · 05-06-2019, 04:24 AM

However, from reading the thread, there also seem to be different generations / software versions of the ZF8 on BMW, so maybe only the latest generation is that good?

E.g. people seem to imply that F30 pre/post LCI have different versions and the newer one performs (much?) better.

///Mvious · 05-06-2019, 07:10 AM

Quote:

Originally Posted by mbanck

However, from reading the thread, there also seem to be different generations / software versions of the ZF8 on BMW, so maybe only the latest generation is that good?

E.g. people seem to imply that F30 pre/post LCI have different versions and the newer one performs (much?) better.

This is true. A decent amount of POST LCI Fxx cars came with the “sport auto ZF8” as standard which is again a step ahead of the regular one. Although I believe this was mostly F3x/F10 LCI. I want to say MY2016 was the yea but not sure

///Mvious · 05-06-2019, 07:18 AM

However, the ZF8 in my 13’ 328i is still running strong and reacts well. And it has been put through 160,000 miles so far. Totally different animal to the sport auto I was referring to. It’s night and day between the two. I still drive new cars that don’t feel as good as early F30s.

kyrix1st · 05-08-2019, 08:46 PM

Quote:

Originally Posted by CntryClub007

So I've been on a journey the last few days...I went and test drove a V10 E60 M5 with SMG, and coming from a POS 320i with 2TB (Sport Auto Trans) coding, I couldn't have been any more disappointed in the M5. I know, this sounds weird, a V10? Yes. The car I loved since I was 15, I no longer love.

The M5 was like driving an Abrams tank. I could feel everything on the road (in a good way), suspension was superb (nice and stiff), steering was tight, brakes were spot on. Car was absolutely immaculate inside and out with 40K on the odometer. Ultimately, it was heavy with a feel of minimal agility.

However, the car just wouldn't "go", I literally asked the driver, this is fully mashed? He's like ya, fast, right? No. I needed to get behind the wheel. So I did, and it was just mediocre at best, it really was. I don't mean this in any rude, insulting way whatsoever to anyone who owns one, but I was just turned off by it all. The engineer in me loves the concept of the SMG and how it works, why it works etc...but it just seems dead with this other technology amongst us now.

Then, I began researching more about the V10, naturally aspirated vs. turbo vehicles, why power comes in at different times, and it really occurred to me that with a boosted motor, the vehicle behaves differently. Coupled to the correct transmission, makes for a pleasant combined and complementary experience.

I can obviously "rip" through the gears with the ZF and launch control in my POS 320i, the SMG was just constant whiplash back and forth on every gear change, I screwed with all of the DriveLogic settings, adjusted my driving style to nail the shifts, the shifting was insanely slow! Granted, I need to read into your entire post, but from what I can gather, it seems like these old school trans are just dead?

So what's the point of my post, not completely sure, HOWEVER, I ended up picking out a 340i, and I pick that up tomorrow, massively stoked to be stepping up in the rankings, so I guess that is cool.

I am willing to bet he didn’t turn DSC off to get shift mode 6.

CntryClub007 · 05-09-2019, 12:57 AM

Quote:

Originally Posted by kyrix1st

Quote:

Originally Posted by CntryClub007

So I've been on a journey the last few days...I went and test drove a V10 E60 M5 with SMG, and coming from a POS 320i with 2TB (Sport Auto Trans) coding, I couldn't have been any more disappointed in the M5. I know, this sounds weird, a V10? Yes. The car I loved since I was 15, I no longer love.

The M5 was like driving an Abrams tank. I could feel everything on the road (in a good way), suspension was superb (nice and stiff), steering was tight, brakes were spot on. Car was absolutely immaculate inside and out with 40K on the odometer. Ultimately, it was heavy with a feel of minimal agility.

However, the car just wouldn't "go", I literally asked the driver, this is fully mashed? He's like ya, fast, right? No. I needed to get behind the wheel. So I did, and it was just mediocre at best, it really was. I don't mean this in any rude, insulting way whatsoever to anyone who owns one, but I was just turned off by it all. The engineer in me loves the concept of the SMG and how it works, why it works etc...but it just seems dead with this other technology amongst us now.

Then, I began researching more about the V10, naturally aspirated vs. turbo vehicles, why power comes in at different times, and it really occurred to me that with a boosted motor, the vehicle behaves differently. Coupled to the correct transmission, makes for a pleasant combined and complementary experience.

I can obviously "rip" through the gears with the ZF and launch control in my POS 320i, the SMG was just constant whiplash back and forth on every gear change, I screwed with all of the DriveLogic settings, adjusted my driving style to nail the shifts, the shifting was insanely slow! Granted, I need to read into your entire post, but from what I can gather, it seems like these old school trans are just dead?

So what's the point of my post, not completely sure, HOWEVER, I ended up picking out a 340i, and I pick that up tomorrow, massively stoked to be stepping up in the rankings, so I guess that is cool.

I am willing to bet he didn’t turn DSC off to get shift mode 6.

Not even remotely close to that. Annoying. Oh well, loving the 340i

CSBM5 · 05-09-2019, 06:35 AM

I think the E60 also default powers on in its lower power mode too? You have to press the power button to allow the throttles to fully open. The S85 is a beast of a motor like the video shows.

PhatLyfe · 05-13-2019, 09:16 PM

These tranny's look ver expensive to replace, the current m4 7 speed's DCT are already cost of one or two kidney's itself.. unless they can make a bullet proof Tranny.. count me out..

Ric in RVA · 05-14-2019, 08:46 AM

One in my 2011 n52 528i and one in my 2010 LR4. Awesome box. Still not a manual. But the only trans I would go with if I could not have a manual.

EstorilM240 · 05-23-2019, 01:06 PM

Probably one of the best in-depth articles about the ZF 8 I've seen is here, with a description of each gear ratio and how it's achieved: https://www.thetruthaboutcars.com/20...eed-automatic/

It's very math heavy, and 5th gear may surprise you!

rlmesq · 05-23-2019, 01:31 PM

I was distracted by how much the guy in the video looks like Beto O'Rourke.

yco · 05-23-2019, 03:43 PM

this guy got old rapidly..

BMWM5NYC · 05-23-2019, 04:36 PM

Quote:

Originally Posted by CSBM5

I think the E60 also default powers on in its lower power mode too? You have to press the power button to allow the throttles to fully open. The S85 is a beast of a motor like the video shows.

Yup. Probably drove in 400 HP mode the whole time.

You actually have to go into the settings and set the "M" button up so when you hit it, it puts you in 507 HP mode.

05-06-2019, 02:59 AM	#70
///Mvious New Member 6 Rep 12 Posts Drives: 05 330Ci SMG, 13 X6 50i Join Date: Jul 2014 Location: boston,ma iTrader: (0)	The way BMW adapts the ZF8 makes it far better than ANY other auto trans. PDK excluded. ZF8 it’s the best auto on the road and the way BMW tunes it to perform is by far the best all around in terms of shift quality/performance and how well it behaves in automatic mode. It downshifts EXACTLY when you ask it to, and hold revs very well given the driving mode you enagage. I’ve driven everything from new Mercs/AMGS, Jags, range rovers , Audi, Alfa’s and New X5/X7/ X3M. I’d have searched for a competitor to bmws ZF8s and nothing comes close. The way BMW tunes it is far superior to others on the road and it’s clear if you switch from a BMW ZF8 to another ZF8.
	Appreciate 2 mkizzo207.00 clee1982804.50 Quote

05-06-2019, 04:24 AM	#71
mbanck Captain 883 Rep 860 Posts Drives: BMW E46 320ci, BMW F10 530d Join Date: Sep 2018 Location: Munich iTrader: (0)	However, from reading the thread, there also seem to be different generations / software versions of the ZF8 on BMW, so maybe only the latest generation is that good? E.g. people seem to imply that F30 pre/post LCI have different versions and the newer one performs (much?) better.
	Appreciate 0 Quote

05-06-2019, 07:18 AM	#73
///Mvious New Member 6 Rep 12 Posts Drives: 05 330Ci SMG, 13 X6 50i Join Date: Jul 2014 Location: boston,ma iTrader: (0)	However, the ZF8 in my 13’ 328i is still running strong and reacts well. And it has been put through 160,000 miles so far. Totally different animal to the sport auto I was referring to. It’s night and day between the two. I still drive new cars that don’t feel as good as early F30s.
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05-09-2019, 06:35 AM	#76
CSBM5 Brigadier General 2897 Rep 3,470 Posts Drives: 2019 M2 Comp, 2011 M3, etc Join Date: Nov 2005 Location: Greenville, SC iTrader: (2)	I think the E60 also default powers on in its lower power mode too? You have to press the power button to allow the throttles to fully open. The S85 is a beast of a motor like the video shows. __________________ Current Stable: 2024 G20 M340i Melbourne Red/Cognac 2019 F87 M2 Competition 6MT, LBB, slicktop, exec pkg 2007 E91 328i Silver, slushbox, Eibach fr/E93 M3 rear sway bars, ARC-8
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05-13-2019, 09:16 PM	#77
PhatLyfe Major 990 Rep 1,143 Posts Drives: 2018 F83 AW/SO ZCP Join Date: Jul 2016 Location: Somerset County iTrader: (0)	These tranny's look ver expensive to replace, the current m4 7 speed's DCT are already cost of one or two kidney's itself.. unless they can make a bullet proof Tranny.. count me out..
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05-14-2019, 08:46 AM	#78
Ric in RVA Bergspyder 1579 Rep 1,247 Posts Drives: '11 BMW 128i Sport 6mt Join Date: Oct 2015 Location: Richmond VA iTrader: (1)	One in my 2011 n52 528i and one in my 2010 LR4. Awesome box. Still not a manual. But the only trans I would go with if I could not have a manual. __________________ Ric in RVA 2011 128i 6 MT Sport, 2009 Cayman 987.2, 2011 528i N52, 2018 F150 Platinum
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05-23-2019, 01:06 PM	#79
EstorilM240 Private 115 Rep 87 Posts Drives: 2017 M240i 6MT Join Date: Jan 2019 Location: California iTrader: (0)	Probably one of the best in-depth articles about the ZF 8 I've seen is here, with a description of each gear ratio and how it's achieved: https://www.thetruthaboutcars.com/20...eed-automatic/ It's very math heavy, and 5th gear may surprise you!
	Appreciate 0 Quote

05-23-2019, 01:31 PM	#80
rlmesq Lieutenant Colonel 1037 Rep 1,508 Posts Drives: 2018 440i M Sport Join Date: Feb 2012 Location: Chico, CA iTrader: (0)	I was distracted by how much the guy in the video looks like Beto O'Rourke.
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05-23-2019, 03:43 PM	#81
yco i'm just saying 6048 Rep 2,634 Posts Drives: E71 X6M '10 (sold) Join Date: Jan 2018 Location: Istanbul & Kyiv iTrader: (0)	this guy got old rapidly..
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