7+ Speed Transmissions: Marketing Gimmick or True Benefits?

Bopop4
That's not a very good argument, you could say the same thing about how there is less stress on the engine due to a larger selection of gears.
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homeforsummer
To play devil's advocate, how do you know it won't have less wear and tear than a gearbox with fewer speeds - given it spends less time in any one gear?...
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There's always two sides of a coin, I guess we're on opposite sides.


Jerome
 
I've driven a few vehicles with an 8 speed transmission, most recently a Ram with an EcoDiesel, and I felt the transmission was fantastic. It didn't shift all the time because the tranny will skip gears if it can and I always felt like the engine was in its powerband. I have no problem with transmissions having more gears, it allows for better fuel economy as well as better performance.
 
peobryant
I've driven a few vehicles with an 8 speed transmission, most recently a Ram with an EcoDiesel, and I felt the transmission was fantastic. It didn't shift all the time because the tranny will skip gears if it can and I always felt like the engine was in its powerband. I have no problem with transmissions having more gears, it allows for better fuel economy as well as better performance.
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I'm not sure if they're exactly the same but same feelings here with the Ecodiesel JGC with the ZF 8 speed
 
I've driven a VW Touareg diesel with an 8 speed transmission and it's fantastic. As @peobryant mentioned they tend to skip gears and combined with the torque of a diesel there's always torque available from low rpm. You can turn absurdly low rpms on the highway but instantly drop a few gears smoothly if you need to pass.
 
I wonder if anyone has ever attempted to use a CVT as a secondary overdrive box? So, say you have a 6 speed manual. You are cruising on the highway at 75mph like normal in 6th gear overdrive But then traffic starts to build up and you are limited to 60mph. Or conversely, you get on a less patrolled section of highway and decide to cruise at 85mph. The CVT could then adjust for the change in cruise speed and you likely wouldn't even notice. Just a thought.
 
Jump_Ace
A gimmicky way to help increase fuel economy by avoiding the higher RPMs. 👎
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Gimmicky? I don't think automotive companies/suppliers spend millions in research on something that's gimmicky, especially when it's a major component like a transmission. I'm also curious how you think there's more wear and tear on the transmission by constantly shifting, it's not like these companies just crammed in more gears without taking into account reliability. You're making an awful specific claim without providing anything that suggests it's true.

On the subject at hand though, I don't think multiple gears in a transmission is a bad thing. Even though a CVT is going to be your best bet for keeping an engine at the most efficient RPM, I think there's still several people out there that have an issue with driving a car equipped with one. I personally don't care for driving a CVT equipped car, I can't get used to it and it doesn't sound or feel "natural" to me, however I have driven a Cherokee equipped with the 9-speed and it worked fantastically. I could see where having more than 6 or 7 speeds in a manual equipped car could be a little annoying, but I think as far as automatics and double clutches go, 8, 9, or 10 gears is good.

Also with the 10-speed in the Raptor, I wonder if some of the lower speeds will act as crawler gears, it'd make sense considering it's built as a showroom off-roader.
 
Eunos_Cosmo
I suppose it's the complexity that troubles me. Imagine how many moving parts a 10 speed auto has. I wonder how much they will cost to rebuild?
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Eunos_Cosmo
I wonder if anyone has ever attempted to use a CVT as a secondary overdrive box? So, say you have a 6 speed manual. You are cruising on the highway at 75mph like normal in 6th gear overdrive But then traffic starts to build up and you are limited to 60mph. Or conversely, you get on a less patrolled section of highway and decide to cruise at 85mph. The CVT could then adjust for the change in cruise speed and you likely wouldn't even notice. Just a thought.
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Ten speeds? Definitely more complex than two entire gearboxes... :odd: ;)
 
Vrr-vrr-vrr-vrr-vrr-vrr-vrr-vrr-vrr-vrr

Probably takes less time to go through ten gears than to read my above replication of it :lol:
 
Especially since, as long as you're accelerating at normal road speeds, it would be more akin to

Vrr-Vrr-Vrr-Vrr-Vrrr-Vrr-Vrr-Vrr-Vrr-Vrrrrrrrrrrrrrrrrrrrrrrrrr

Odds are, unless you have your foot planted, the transmission will be smart enough to know which gears to engage and which gears to skip. Which in the end means smoother shifting because the transmission can choose the more optimal gear than if it were limited to 6. From what I've driven, a well programmed, responsive 8 speed delivers as smooth an experience as the CVT in my mom's Outback without the cost, maintenance, or lag of a CVT.
 
I can imagine that at twelve speeds... four gears and three final drives... you're about done. Bicycles nowadays have more than that... except the luddites who ride fixed speed bikes. Yeah... they're the same guys driving classic cars... :lol:

I actually drove a five-speed previous-gen Impreza with a transfer case a few years ago. Technically ten speeds, though going through them sequentially would take a map and an extra pair of hands.

RE: peak torque/hp: No matter how flexible your powerband is, your car will always accelerate best at peak hp:

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579731_10151865932797841_501269264_n.jpg

(Feels like decades since I made these graphs)

Even with a torque curve like a mountain, it's worth holding a lower gear till the hp peak. Even on cars where I've found it beneficial to short shift (during drag-strip testing), the optimum shift points still came after peak hp.

With more speeds, you can stay near that peak longer. And with DSGs, the torque interruption is so inconsequentially short that you don't suffer a loss of speed for each shift. With newer CVTs with better torque converters, you don't even have to leave that peak hp rpm. Ever.

With manuals, the torque interruption sometimes means its better to hold a gear a bit longer rather than wasting time shifting. Unless you like destroying synchros.

I don't see manuals going much further than seven or eight gears on a single stick (indeed, damaging mis-shifts are already annoyingly common with just six speeds). Not without a fundamental redesign of the standard shift pattern...
3e34835f655f03f09b83f5c7b707a96b.jpg
 
Basically this:

Shift at or close to Max Torque for comfortable daily driving, and Max HP for Outright-speed.

On high RPM N/A engines this tends to be Unrealistic though as Max Torque is too high.

But these engines tend to not be efficent at daily usage.
 
My car is a 2002 3-cylinder Vauxhall/Opel. It's fuel injected though the engine itself is from around the industrial revolution. 5 Speed Manual. I would be chuffed off my tatti-bojangles if it had 6 gears. I like the way the Vipers and Corvettes seemingly worked it. Top gear was relatively wide almost like an overdrive, for motorway economy.

My car sits at just over 3000rpm at 70mph. It makes quite a racket over about 2100rpm. So, a 6th gear would be wonderful. 6 seems like the perfect number for me, especially on a manual. What with engines getting more accessible, I struggle to see a need for more than 7 speeds in an auto. There was once a day when auto 'boxes had even less gears than the manuals (I'm looking at you, '63 Chevrolet Corvette!).

My Dad would have been chuffed if his mum's Renault 4 had 5 gears... oh wait, he hated it. Never mind.
 
mustafur
Basically this:

Shift at or close to Max Torque for comfortable daily driving, and Max HP for Outright-speed.

On high RPM N/A engines this tends to be Unrealistic though as Max Torque is too high.

But these engines tend to not be efficent at daily usage.
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I shifted at around 3500-4000rpm in my RX7. Because rotary.

I also got 8mpg.
 
niky
Truck shifter. And while it's often posted as a joke, the real thing is almost as bad...
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Car and Driver did a "How To" article on shifting a semi a few years ago. It sounds hard. Though I've never actually driven a proper car. Last year I went to a go kart track, but they weren't shifter karts.
 
Naveek Darkroom
Car and Driver did a "How To" article on shifting a semi a few years ago. It sounds hard. Though I've never actually driven a proper car. Last year I went to a go kart track, but they weren't shifter karts.
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I have yet to fulfill my ambition of doing a full-on road test of a semi.

Might get my chance... Foton has an 11 liter 400 hp diesel cab in their showroom... :lol:
 

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