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Is an 8 speed automatic transmission the most gears we will see?

rockyleerockylee Wyoming, MichiganPosts: 13,989
edited September 17 in BMW
Six is for Peasants: ZF Unveils 8-Speed Automatic

http://jalopnik.com/cars/news/six-is-for-peasants-zf-unveils-8+speed-automatic-2- - 57432.php

This Johnny guy says we could see a 10 speed automatic by 2011 unless DSG's replace conventional automatics :surprise:

http://blogs.edmunds.com/Straightline/2713

-Rocky

Comments

  • drfilldrfill Posts: 2,484
    Toyota seems ready to switch over to CVT, with their Hybrids, and since they are the pole-setter, I think a 9 or 10 speed would be a waste.

    Not that someone won't do it. Because someone will.

    Where do you draw the line? I say 8-speeds. ;)

    DrFill
  • rockyleerockylee Wyoming, MichiganPosts: 13,989
    Well like you old, old, timer's bikes 10 speeds might be the limit. ;) I would still like to see a 18-speed manual like the Semi's I use to drive.-grin :P

    -Rocky
  • lemkolemko Posts: 15,189
    ...with my old-fashioned 4-speed automatic in my 1988 Buick Park Avenue. I shudder to think what the repair/replacement costs of an 8-speed tranny would be. Of course I would see a lot of children of trans techs going to Ivy League schools.
  • geo9geo9 Posts: 739
    My buds momma had a older suburu justy with that CVT
    automatic trans...............

    Didn't GM have a similar setup in Novas years back?
  • geo9geo9 Posts: 739
    On those GM 4 speed autos !!!!!!!!!!!!!

    My new 6 speed Chevy truck is one busy tranny!
    We will see how it holds up heavy towing or snowplowing..

    I note the many complaints on the camrys new trans.
    But the toyo faithfull non owners are telling the poor
    folks with issues that they are either crazy, troublemakers,
    or trolls...........LOL!!!!!!!!!

    Some folks are never happy no matter how many useless
    speed trans. are in a passenger car !!!!!!!
  • sls002sls002 Posts: 2,788
    cvt's are not as fuel efficient as hoped for. the prime reason for going to more speeds is to improve fuel efficiency and performance. I don't think that GM's six speed will be that much much expensive to repair and with more gears the transmission fluid may stay cooler if the torque converter does less work. I think that to get six speeds there are probably 3 planetary gear sets. Probably 7 or 8 speeds can be made available from 3 planetary gear sets, so an 8 speed transmission would not have to be that much more complex.
  • rockyleerockylee Wyoming, MichiganPosts: 13,989
    Did I read somewhere that GM, is working on a 7 or 8 speed automatic for Saab ?????

    -Rocky
  • lemkolemko Posts: 15,189
    ...I'd rather just stop at 4 gears. More gears = more $ for the transmission shop guy! It already costs a minimum $2,500 for a tranny repair these days. I wonder how many more $ it takes for each added gear? Does it add or multiply? :sick:
  • andre1969andre1969 Posts: 22,008
    I think sometimes it just depends on the transmission. I remember back in 1998 when I bought my '89 Gran Fury, from a place that refurbishes old police cars and sells them to the public, they told me that it cost around $1800 to rebuild the 4-speed automatic that late 80's Caprices were using. However, this wasn't the lighter 200R4 tranny (like what's in your Fleetwood, or my old '85 LeSabre) but a beefier tranny. I think it was the tranny that ultimately became the current 4L60E truck tranny. At that time, it would've cost around $650-700 to rebuild a 3-speed Torqueflite like what the Gran Fury had. And used ones were a dime a dozen, simply because they rarely failed, so there were plenty available out of junkyard cars. They told me that if the tranny ever failed, they could put in a used on for around $300!

    One of the managers at work here had a 1987 Buick Electra Estate wagon with that lightweight 200R4 tranny. He had to have it replaced at some point, but I forget how many miles it had on it. He did a lot of towing with it. I think it cost around $2200 to replace, but he had the dealer do it, which probably inflated the bill.

    Last tranny rebuild in my family was my uncle's 1997 Silverdao, back in the Spring of '06. It has the 4L60E tranny, and it started to fail. Reverse went out, along with 2 of the 4 forward gears, but I forget which two. It was around $1860 to have rebuilt, at a local tranny shop.

    I've heard that the 4-speed they use in cars, like your '88 Electra, are actually fairly inexpensive to rebuild.
  • robertsmxrobertsmx Posts: 5,525
    8-speed auto is nothing new. Toyota has been using it in Lexus LS and soon to be put in Lexus IS-F.

    When it comes to “speeds”, there is little to no point beyond 6-speed auto unless the losses could be reduced (but with same technology, they could be with fewer cogs too) and gearing span increased. The Mercedes 7-speed auto is a classic example of this. It has an exceptionally tall top gear, perhaps too tall for most practical purposes, a reason it is very close to the next shorter gear (seventh gear is 90% of sixth). Despite this extra tall ratio, the span hasn’t been increased. It is still around 6, which is the norm for 6-speed automatic and CVT. I don’t see an advantage in this case.

    Now, if the gear span could be increased, we might be looking at something interesting, as it would allow very short low gears coupled to relaxed tall gear (gear span = first gear ratio/top gear ratio).
  • steverstever Viva Las CrucesPosts: 40,860
    I'm racking my brain trying to remember if I read an article somewhere about manually shifting a seven or eight speed transmission. It seems like some reviewer complained that matching revs was difficult when downshifting (I'm assuming that was with paddle shifters).

    Maybe it's just some sour grapes?

    Good article about the power, emissions and fuel economy of seven and eight speed trannies:

    A Little Knowledge of Transmissions Can Save You Big Bucks at the Pump

    Moderator
    Need help navigating? stever@edmunds.com - or send a private message by clicking on my name.

  • lemkolemko Posts: 15,189
    ...with more gears, but they're in semi trucks.

    From wiki:

    Because of the wide variety of loads the "semi" may carry, they usually have a manual transmission to allow the driver to have as much control as possible. However, all truck manufacturers now offer semi automatic transmissions (manual gearboxes with automated gear change) as well as automatic transmissions.

    "Semi" truck transmissions usually provide at least nine or ten gear ratios, but possibly as many as eighteen (e.g. Australian Road Trains). A large number of transmission ratios means the engine itself can operate within a narrow range of speeds. The range of speeds over which an engine is expected to perform well has implications for the design - the narrower the range, the more the engine can be optimised for that. Also having so many gears allows fine-grained control of engine braking for better control on downhills and in curves.

    A ten speed manual transmission is controlled via a six-slot H-Box pattern similar to that in five-speed cars - five forward and one reverse gear. Gears six to ten (and high speed reverse) are accessed by toggling a selector control - so that first gear becomes sixth, second becomes seventh, etc.

    Another difference between semi-trucks and cars is the way the clutch is set up. On a regular car the clutch pedal is depressed full stroke to the floor for every gear shift to ensure the gearbox is disengaged from the engine. On a semi-truck with e.g. Eaton Roadranger series constant mesh transmission (non synchronized) not only double clutching is required, there is an additon of clutch brake as well. The clutch brake stops the rotation of the gears and allows the truck to be put into gear without grinding when stationary. The bottom of the clutch pedal stroke is where the clutch brake activates and as a result only partial or "half" clutch pedal stroke is used when a vehicle is in motion.
  • the amount of tranny repair is about the same there is no more work on 7/8 speed tranny then a 4/6 speed. its just a bigger trany
  • oldbearcatoldbearcat Posts: 170
    I've got a Mercedes GLK350 4matic with the 7 speed. With the nice flat torque curve the Mecedes 3.5 liter 6 has, the little SUV has no problem holding 7th gear on my interstate runs, even going up fairly steep grades ( I live in WV so there's plenty of them on our interstates). In addition, the GLK is quite quick for a SUV.

    Regards:
    Oldbearcat
  • andre1969andre1969 Posts: 22,008
    In your opinion, do you think your Benz could get by with fewer gears, or do you feel that they benefit you? Since you live in a mountainous area, I'd imagine that you'd see some extra benefit to those additional gears.

    I have to admit, the only thing I've ever driven with seven gears is a 1990 Montgomery Ward lawn tractor! :P I've driven my buddy's 2006 Xterra a few times though. It has a 5-speed automatic, and I don't really care for it. It seems to have no power in top gear, and when you need to stomp it and downshift, it seems like there's a slight delay, but then it kicks in and almost seems to take off TOO fast, as if it's compensating for that lag.

    I'd probably get used to it if I drove it on a regular basis, but most of my driving is done with archaic 3- and 4-speed automatics, so to me that 5-speed just seems like it shifts too much. It doesn't lurch or clunk, but I can still feel it from the change in engine revs.

    I used to think that my old 2000 Intrepid would have benefited from an additional gear. Sometimes in 4th gear, it would get a bit gutless, but then when it shifted to 3rd, it almost seemed like overkill. FWIW, at 75 mph, 4th was 2500 rpm and 3rd was around 3750. If they had stuck an additional gear somewhere between 3rd and 4th, I thought it would help a bit.
  • Most drivers of "roadranger" equipped trucks don't bother with using the clutch, except for stopping and starting.......shifting is done 'by ear' and/or watching the tach. Takes some practice.
  • oldbearcatoldbearcat Posts: 170
    Andre:

    IMO the 7 speed certainly enhances the GLK's performance. The car I traded for it was a Jaguar S-Type V8 with the 6 speed automatic. Both cars have enough low RPM torque that they don't frequently downshift on hills at interstate speeds. The ZF transmissions shift almost seamlessly as well. I had a 2001 Intrepid with the 2.7 - I know what you're talking about. My business driver is a Honda CRV - with a 5 speed automatic. It makes you crazy downshifting to as low as 3rd while it screams its guts out climbing a hill on the interstate.

    Regards:
    Oldbearcat
This discussion has been closed.