ProDarwin wrote: Big rigs have manual control and have 15ish gears.
They also have a much narrower band of usable engine RPM, which makes the extra gears more necessary. It also makes it harder to be in a gear that's more than a little bit wrong.
ProDarwin wrote: Big rigs have manual control and have 15ish gears.
They also have a much narrower band of usable engine RPM, which makes the extra gears more necessary. It also makes it harder to be in a gear that's more than a little bit wrong.
Adrian_Thompson wrote: With traditional autos we're up to 10 forward and 2 reverse gears.
Are automakers actually using 2 reverse gears? The only use I could think of for that is one "high torque" reverse gear for backing up a heavy trailer and one "high speed" reverse gear for Rockford-style J-turns, but I can see stability control trying to prevent a J-turn.
The 7 speed auto in my CLS63 has 2 reverse gears, a taller one used in comfort mode and a shorter one when sport mode is selected. You can feel the difference.
Schmidlap wrote:Adrian_Thompson wrote: With traditional autos we're up to 10 forward and 2 reverse gears.Are automakers actually using 2 reverse gears? The only use I could think of for that is one "high torque" reverse gear for backing up a heavy trailer and one "high speed" reverse gear for Rockford-style J-turns, but I can see stability control trying to prevent a J-turn.
I could see this. Normal gear for normal reversing. Steep gear for when you are backing up the 10,000lb trailer, uphill.
Sonic wrote: The 7 speed auto in my CLS63 has 2 reverse gears, a taller one used in comfort mode and a shorter one when sport mode is selected. You can feel the difference.
So what's your backwards 1/4 mile time?? 
One thing I'm really tired of are all the different manufacturer brand names for a small handful of the same technologies.
PDK (Porsche) / DSG (non-Porsche VAG) = dual-clutch robotized manual. Most supercar manufacturers use the proper technical term, props to them.
Tiptronic/Geartronic/Sportronic/SportShift/S-Tronic/and a million others = Manually shifted planetary auto.
Flappy Paddles (Jeremy Clarkson / colloquialism) = implies dual-clutch robo-manual but manually shifted autos often also have flappy paddles.
In reply to GameboyRMH:
The only way you will fix that is to have SAE define, as an industry, the technology. Otherwise, everyone is going to call them different. It's been that way since the dawn of marketing.
In reply to GameboyRMH:
Posi traction
LSD
Lockers
Track loc
Automatic
Hydromatic
Geartronic
E-tronic
Powerglide
etc.
You'll never get people to agree to the same name for the same thing when you can try and pretend your version is better than the competitions.
My personal opinion is that more and more vehicles will begin using a 'hybrid CVT' design as originated by the Prius and now adapted and adopted by MANY others. It's simple, gives tons of flexibility, and is extremely reliable.
As for conventional planetary-based autos being a full replacement for 'manual-style' gearboxes such as true manuals and dual clutch automated manuals, that's really only plausible if you've never been inside a planetary-based auto. There are WAAAAAY more parts, and more spinning weight, and more contact points, more parasitic friction losses, and pumping losses to keep it all lubricated and supply pressure for the holding elements. So while you can get planetary-based auto trans to have all the same ratios and shift nearly as quick as an automated manual, you will never make it as simple or have as few failure points. Of course, YMMV depending on the actual execution of whatever two boxes you're comparing. Some manufacturers build very complicated pieces that work forever, and some build simple things that still manage to break.
My main beef with both 'conventional' CVTs and dual clutch boxes is the 'start clutch' behavior. You can make it good, but you can never make it as good as a torque converter, imo. I wish manufacturers would use torque converters (still with lockup clutches, mind you) on both designs more often.
I also wish someone would build a torque converter that used magnetorheological fluid so you could vary stall behavior with an electrical current. Launch control that doesn't burn up start clutches, here we come. 
You could even use such a thing to eliminate the need for a ratio or two on the lower end.
The Regera does NOT use a multispeed transmission of any kind. It uses a VERY robust and specialized torque converter and a single gear reduction in the differential. It's a perfect example of what i just mentioned, just taken to an extreme. It has enough torque between its power sources (including a big electric motor between the torque converter and diff) to eliminate ALL the gear ratios except the diff, because of what that special converter allows it to do! In some ways it is very similar in operation to the Accord Hybrid someone mentioned earlier. 
dculberson wrote:GameboyRMH wrote: In a logical world the CVT would replace the planetary automatic in non-performance applications within 5 years, and the robotized manual would be the standard in performance applications.I've heard a lot of reliability problems with almost everyone's CVTs. Maybe they're not all they're cracked up to be. Efficiency might be better but if it's not paired with reliability then there's no contest which I would choose.
Subaru's are great. Nissan's are junk.
I dunno about the reliability of them, but I have to give the CVT in the 2016+ Civics some credit. At least with the turbo-4 in front of them, they're the first CVT I've driven that didn't make me want to jump off a cliff.
GameboyRMH wrote:dculberson wrote:Subaru's are great. Nissan's are junk.GameboyRMH wrote: In a logical world the CVT would replace the planetary automatic in non-performance applications within 5 years, and the robotized manual would be the standard in performance applications.I've heard a lot of reliability problems with almost everyone's CVTs. Maybe they're not all they're cracked up to be. Efficiency might be better but if it's not paired with reliability then there's no contest which I would choose.
Given the small number of CVT suppliers, it's likely that the two both use an Aisin CVT.
alfadriver wrote:GameboyRMH wrote:Given the small number of CVT suppliers, it's likely that the two both use an Aisin CVT.dculberson wrote:Subaru's are great. Nissan's are junk.GameboyRMH wrote: In a logical world the CVT would replace the planetary automatic in non-performance applications within 5 years, and the robotized manual would be the standard in performance applications.I've heard a lot of reliability problems with almost everyone's CVTs. Maybe they're not all they're cracked up to be. Efficiency might be better but if it's not paired with reliability then there's no contest which I would choose.
It could be the exact same transmission! Subaru could be bolting it to an engine peaking at 130 lb ft and Nissan at 180 lb*ft.
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