SouthernSon

The only time I ever use the paddle is in touring mode, on the street and coming to a stop just to listen to that marvelous burble sound emanating from the exhaust. It is as intimidating as a T-rex clearing his throat! Now on the road course I like the lightning fast shift of the auto mode and have learned that the programming is pretty darn good. Of course there will always be some that leave out that mode while bashing the ZR1 auto and simply tell half truths (fake news). The auto is faster and although I have a 1st place trophy or two with a manual on the road course I have nothing but praise for the auto. Sure, I like shifting on the street in my '96 LT4 (ZF6 transmission - heavy truck tranny actually) from time to time and my C5Z on track but it is going to take a lot more than half truths to quell my enjoyment of my ZR1 auto. There is nothing wrong with the M7 but there sure ain't a damn thing wrong with the auto, either.

TLS_Addict

Real question here around the A8 and A10 because I haven't seen it mentioned.

I am considering a new ZL1 but am pretty much a manual tranny only guy but the A10 from my research seems really great. So here goes.

Though the A10 shifts faster but is the quickness of the gear change enough to offset less gear changes being made by the A8? I haven't looked into peak rpm in each of the gears for both transmissions. But just a scenario that if the A8 needs 4 gears vs 5 for the A10 to reach the same speed and the A8 shifts each gear at .25 x 4 would be 1 and the A10 would shift each gear at .2 x 5 which would allow equal 1......is the A10s ability to keep the engine in it's optimal power band the deciding factor?

Again, arbitrary numbers just to start a conversation. I'm a manual guy but if manual guys are leaning towards automatics maybe I should try one. And as many of you know I'm not a C7 fan but the changes to the ZR-1 fix 95% of what I don't like with the C7. lol But I would need for prices to come down for me to grab one.

SouthernSon

I haven't read a comparison of the A10 vs. the ZR1 A8. Have you? The only mention of the A10 being faster that I have read concerns comparison to older/other autos used in the camaro, not the 2019 ZR1. Don't go believing the half truths on this forum that the A10 is faster than the '19 ZR1 A8 (which had some special treatment for the ZR1 according to GM). If you have an actual published article with direct comparison I would certainly be interested.

TLS_Addict

I was speaking in generalities of the A10 to last published figures of the A8. I don't know the difference of the 2018 and prior A8 vs the 2019 ZR-1 A8.

If anyone has it I would love to see it as well.

94Lt1Vette

The idea that a Camaro transmission might be better is really eating at you, isn't it?

SouthernSon

If it were true, it would not. Does the fact that you don't know how the ZR1 A8 and A10 compare because you can't find a one on one comparison bother you? The best you can come up with is how the A10 is better than some previous ones for the camaro in some respects, but even then, perhaps not all. You can't find anything that details all the tweaks GM put into the A8 for the '19 ZR1 for a direct comparison. But, you keep digging and let us all know if you find anything.

94Lt1Vette

Have you ever driven the 10 speed?

range96

Oh yeah, when I was 12.

Hib Halverson

Any good transmission shop or a GM dealer will have a piece of equipment which can replace the fluid. They connect to the trans cooling system and do not fill the trans though the rubber plug used to manually fill the trans.

Once it's connected, the machine's reservoir is filled with the new fluid and the machine is turned on. In the reservoir there a moving separation. The old fluid (11-12-qt) is sucked into one chamber and the new fluid fills the trans from the other. The machine is disconnected. Then the engine is started and idled until the trans reaches the check temperature, then it goes up on the rack and the fluid level is checked by removing a bolt at the corner of the pan. If you can see fluid just at the edges of that hole, you're ok. If it's too high, fluid will dibble out of the hole until the level is correct. If it's too low, the edges of the hole will be dry and you have to pump a little more fluid in through the fill hole.

Hib Halverson

Ya know, on this 8L90 vs 10L90, I really don't have a dog in that fight, because I think they are both pretty good automatics, but I am interested to know, since this is obviously become a very partisan discussion, what are you guys using to actually measure these shift times with which you are so concerned. I mean we're talking 1/10ths of seconds or less. It's gotta be some pretty sophisticated testing equipment.

Inquiring minds want to know.

SouthernSon

I am amazed you find time to try to deflect. You might try different search engines for the direct comparison of '19 ZR1 A8 and the A10 transmission. Be sure to take a break every now and then for a bite to keep up your strength.

94Lt1Vette

Well, if you had driven both, you could give us a direct comparison

GM does a direct comparison in the gear ratios, which helps do a better job of keeping the A10 in the power band longer. https://media.gm.com/media/us/en/gm/...0speed-gm.html

They do a good comparison, albeit without shift numbers.



What is different about the ZR1 A8 vs a Z06? Are they not both 8L90s? Just programming, right?

Try the 10 Speed for yourself. You'll see why most people believe it's a superior transmission. The only reason it didn't make it into the ZR1 was fitment, otherwise I guarantee you'd be sitting here singing about how it's the best transmission ever instead of trying to pass off the "tuned A8" as anything more than average.

SouthernSon

An assumption on your part. It could actually be the reason they gave the ZR1 A8 special treatment. Did that special treatment make it even better than the A10 in the corvette platform? I don't know and I surely don't think you know. Try not to let your prejudice influence your assessment of the facts and the conjecture.

d16dcoe45

You nailed it 100% and I think this it is funny but at the same time horribly sad☹️. The Hellcat/392 ZF A8 is another superior automatic transmission, but Southern Son would NEVER concede that! He uses every trick he can to protect his ego. I almost think he is kidding when he responds. It is the excuse making and petulance you expect from a 10 year old.

Just give credit where credit is due.

What a fabulous piece of engineering!
https://www.google.com/amp/gmauthori...on-defect/amp/

SouthernSon

Facts get really pesky for you, huh? Still waiting for that direct comparison of the two transmissions. Anyone?

d16dcoe45

The reason there is no DIRECT comparison is because the 8 speed is still in the FLAGSHIP Corvette so GM is not going to blatantly say the 10 speed is better but if you actually READ THE ARTICLE you will see the improvements. It is regarded as the BETTER transmission. That is not my opinion, that is fact. I don't know if you are fooling with me or being a wiseguy but if you are being this recalcitrant and stubborn to accept the truth, then I really don't what to say. Your mental stability is questionable. It doesn't matter WHAT you think, the truth is the truth.

Holy Shift! A Look inside GM’s new 10-Speed Automatic

Advanced design, GM control system support capability, enhanced efficiency

2016-05-11




Print Email Word

DETROIT – Engineers for the new 10-speed automatic transmission available in the 2017 Chevrolet Camaro ZL1built on the experience of previous, critically acclaimed Hydra-Matic multispeed transmissions to push its performance, refinement and efficiency advantages to a new threshold.

The 10-speed is an all-new design – and the first-ever application in a car – with a wider, 7.39 overall gear ratio spread, that enables the ZL1’s supercharged engine to remain at optimal engine speeds during upshifts.

“With world-class shift times on par with the world’s best dual-clutch transmissions and the refinement that comes only from a true automatic, the 10-speed delivers incomparable performance on and off the track,” said Dan Nicholson, vice-president, GM Global Propulsion Systems. “It also leverages the experience of our other multispeed transmissions to deliver that performance with greater efficiency as its use expands into other vehicles.”

The wider overall ratio enables a lower numerical top gear ratio – an attribute that reduces engine speed on the highway, which contributes to greater fuel efficiency than a comparable eight-speed transmission. Improvements in spin loss complement the optimized gearing, further enhancing efficiency.

And while the Camaro ZL1 will be the first GM vehicle to offer the new 10-speed automatic, designed for rear-wheel-drive applications, it will be available in eight additional vehicles by 2018.

Additional highlights:

• Creative packaging – The 10-speed is approximately the same size as the six- and eight-speed transmissions, minimizing changes to vehicle interfaces.
• Quicker shifts than a dual-clutch transmission – Testing has shown faster upshift times than the Porsche PDK dual-clutch transmission. In fact, the 1-2 upshift is 36-percent quicker than the PDK, while the 2-3 and 3-4 upshifts are 27-percent and 26-percent quicker, respectively.

• Reduced spin losses – Thanks to only two non-applied clutches – the same number as the eight-speed – as well as other design features, the 10-speed automatic has lower friction that contributes to greater fuel efficiency over GM’s six- and eight-speed automatics. New ultra-low viscosity transmission fluid also reduces friction, while an internal thermal bypass allows the transmission to warm up faster – attributes that enhance fuel efficiency
• GM-developed controller – It is the latest transmission to use an all-new, GM-developed control system, with performance calibrations tailored specifically for different vehicles.

Architectural features and packaging
Thousands of hours of computer-aided engineering analyses were made during the development of the Hydra-Matic 10-speed transmission, driving a comparatively compact design envelope comparable to the eight-speed automatic.

A one-piece aluminum case with an integral bell housing helps reduce weight and enhance powertrain stiffness, while a unique 260mm, integral turbine clutch torque converter design reduces complexity and helps make the converter thinner, which contributes to the transmission’s packaging.

The 10-speed has four simple gearsets and six clutches: two brake clutches and four rotating clutches. That’s only one more clutch than the eight-speed, despite having two more forward gears, contributing further to the compact packaging, while also improving spin losses to enhance fuel efficiency.

A unique triple-clutch assembly in the middle of the 10-speed’s architecture is a primary enabler for packaging 10-speed content in the same space as GM’s six- and eight-speed transmissions.

The 10-speed also features a variable-displacement vane pump, which optimizes transmission fluid pressure, based on speed and load, to enhance efficiency.

7.39 ratio spread and faster upshifts
The new 10-speed’s greater overall performance and efficiency are due primarily to its wider 7.39 overall gear ratio spread, which enhances off-the-line performance with a more aggressive first gear ratio than GM’s eight-speed automatic. Smaller steps between the gears also help the engine maintain the optimal speed for maximum power at almost all speeds, especially when exiting a corner on a track.

Adaptive shift controls such as Performance Algorithm Shifting and Driver Shift Control enhance performance driving. Performance Algorithm Shifting (PAS) monitors how assertively the driver is using engine output to determine at what engine speed to upshift or downshift. Driver Shift Control allows the driver to shift the transmission via the steering wheel-mounted paddle shifters. Electronic safeguards prevent over-revving if the wrong gear position is selected, but relies on the driver to make upshifts or downshifts.

Gear changes are mainly executed with clutch-to-clutch action, where an “on-coming” clutch is engaged and an “off-going” clutch is released in a precise manner to achieve the ratio change. Certain key shifts, however, are made with a freewheeling action, such as 3-1 downshifts, where a plate clutch is actively disengaged while a mechanical freewheeler clutch automatically engages with optimum synchronization.

The torque converter is 260mm in diameter and features a lock-up clutch. It also uses electronic controlled capacity clutch (ECCC) technology, which employs a small, regulated amount of slip to dampen out engine pulses for a smoother running drivetrain, especially during shifting.

GM Hydra-Matic 10-speed vs. eight-speed gear ratios

Type:

10-speed automatic

eight-speed automatic

Gear ratios (:1)





First:

4.70

4.56

Second:

2.99

2.97

Third:

2.15

2.08

Fourth:

1.80

1.69

Fifth:

1.52

1.27

Sixth:

1.28

1.00

Seventh:

1.00

0.85

Eighth:

0.85

0.65

Ninth:

0.69

--

Tenth:

0.64

--

Reverse:

4.87

3.82



Reduced spin losses and new transmission fluid
Friction-reducing design features, including all-new ultra-low viscosity transmission fluid, internal thermal bypass, minimal number of non-applied clutches and otherlower mechanicalspin losses, contribute to the 10-speed’s effect on improved vehicle efficiency.

The low-viscosity fluid helps reduce fraction across the full temperature operating range, which enhances fuel efficiency. Additionally, the internal thermal bypass allows the transmission to warm up faster to its optimal operating temperature, further contributing to fuel efficiency.

GM control system
World-class shift time quickness and responsiveness are accomplished by leveraging the base transmission hardware in concert with GM exclusively developed algorithms, software and calibrations. An externally mounted electronic control module executes millions of controls instructions every second

NW-99SS

Can't understand why we are still talking about the A8 vs A10?

Facts (already posted and linked in this thread):

The A10 is too big to fit in the C7

The A8 is the only automatic available to the ZR1

The A8 has known issues, TSBs, and a class action lawsuit filed against GM for its issues (hard shifting, torque converter shudder, etc).

At the end of the day, the C7 will never see the A10 - regardless if it's better or not (I think the answer is clear to almost everyone in the performance world). This thread started about M7 or A8 for the track...

d16dcoe45

You are absolutely right. My apologies for bringing it up again. The thread is over the current A8 or M7 and which is better for the track. Again, sorry for going off on a tangent.

serpent

So.... what about a DCT? Lol

d16dcoe45

😂😆🤣