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    • 9-speed transmission? Yep. Mercedes-Benz replaces 7G with 9G-Tronic automatic with nine gears

      Thought a seven speed transmission was enough? Well think again, as Mercedes-Benz is launching a 9G automatic transmission offering as the name suggests nine speeds. The goal of course being efficiency and increasing highway fuel economy figures by keeping the motor at lower revs. The new 9G transmission is standard equipment on the E350 BlueTec and should replace the 7G in all standard models eventually but likely not in AMG models. The 4Matic E350 will stick with the 7G for now.

      Cramming more gears into an automatic housing rarely makes the transmission stronger. AMG stuck to the old 5-speed automatic for quite some time in AMG cars due to the torque they generate. Only recently have they switched to the 7G in the big torque 65 AMG models and it is doubtful the 9G is up to the task of 738 pound-feet of torque.

      The 9G transmission improves fuel economy figures by 2 miles per gallon on the highway in the E350 BlueTec. City figures improve by a surprising 3 miles per gallon. 0-60 remains 6.6 seconds.

      Will transmissions stop here or add more even more speeds? Considering 7-speeds have now become routine and the same will likely happen with eight and nine speeds one should not bet against it.


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      This article was originally published in forum thread: 9-speed transmission? Yep. Mercedes-Benz replaces 7G with 9G-Tronic automatic with nine gears started by Sticky View original post
      Comments 13 Comments
      1. klipseracer's Avatar
        klipseracer -
        More gears becomes feasible with better and faster shifting technology. Makes a person think the CVT idea was the best due to near infinite gearing ratios, if only it were a stronger solution.
      1. Sticky's Avatar
        Sticky -
        Ya CVT is just too weak.
      1. Torgus's Avatar
        Torgus -
        f cvt...
      1. whoosh's Avatar
        whoosh -
        A strong CVT would be the ideal transmission. You could tune the motor/trans to work together to keep things at the optimal torque or HP point based on specific conditions. They definitely aren't the most exciting thing to drive (sounds like whaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa!!!!! !!) and the Fast and Furious franchise would definitely miss out on some big drama scenes... HaHa

        as for 9 speeds, seems like at some point the added weight of the extra gears and larger casings would offset any gains in efficiency.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by whoosh Click here to enlarge
        as for 9 speeds, seems like at some point the added weight of the extra gears and larger casings would offset any gains in efficiency.
        I wonder when that point will be.
      1. crniamg's Avatar
        crniamg -
        9 speed wow nice it's like from Jacksonville to Daytona i wont use all the gears Click here to enlarge more valve body issue and speed sensors i hope not
      1. klipseracer's Avatar
        klipseracer -
        My A4 has the CVT. In sport mode it can certainly act like a normal car. In D, its so $#@!ing dull and feels like the ultimate dog. But I get great gas mileage. Which is then cancelled out by the premium fuel I have to run.
      1. crniamg's Avatar
        crniamg -
        o i love gas mileage on my gl450 7 speed after GMC Yukon
      1. nielsll's Avatar
        nielsll -
        Press release specs show that it can handle torque from the M279 and is lighter weight. Still a torque converter transmission.
      1. mjmarovi's Avatar
        mjmarovi -
        Gas mileage? I mean, not gonna say I don't mind getting 25-27 mpg on a car that runs 12's at the track, but honestly, not the reason I bought it. IMO anything that gets over 20 mpg on highway is good enough. If it's a sports car, who cares. lol

        for those buying for fuel efficiency though, it's good news. I personally will leave fuel efficiency to the Japanese and their hybrids...
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by nielsll Click here to enlarge
        Press release specs show that it can handle torque from the M279 and is lighter weight. Still a torque converter transmission.
        I'll believe it when I see it.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by mjmarovi Click here to enlarge
        Gas mileage? I mean, not gonna say I don't mind getting 25-27 mpg on a car that runs 12's at the track, but honestly, not the reason I bought it. IMO anything that gets over 20 mpg on highway is good enough. If it's a sports car, who cares. lol

        for those buying for fuel efficiency though, it's good news. I personally will leave fuel efficiency to the Japanese and their hybrids...
        That's how it should be.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge