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I have a 2016 SLK 300 with a 9 speed tranny. On the dashboard part that tells you what speed the tranny is in, it only goes up to 8. I tried to paddle shift it to 9, but it doesn't go any higher then 8. I am confused as to how to get it to 9th gear. WTF?:surprise:
 

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* Founding Member #2
2008 SLK55 AMG
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Maybe you are not at the "correct" speed for it to go from gear 8 to gear 9? Did you see any "warning" icons when trying to manually up-shift.
Do you have the tranny in manual mode or sport mode?
 

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I suspect that unless you are on a track, you aren't going to get it to a speed where the car will let it go to 9.
No, the top gear is usually what is used on the highway at cruising speeds.

On the 7-speeds, after 6 the top gear is shown as "D", there isn't a numeral 7. Is this also the case with the 9-speeds, where you can see a "D" after 8?
 

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No, the top gear is usually what is used on the highway at cruising speeds.

On the 7-speeds, after 6 the top gear is shown as "D", there isn't a numeral 7. Is this also the case with the 9-speeds, where you can see a "D" after 8?

That's not true for my 7 speed box - top gear is shown as 7 (not D) and can be engaged as low as 45/50 mph...
 

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That's not true for my 7 speed box - top gear is shown as 7 (not D) and can be engaged as low as 45/50 mph...
Which corresponds to how many engine revs?

I suspect the 9-speed adds the extra gear somewhere in the current range and adds one slightly higher than now. There will be some cunning VAG-style gear-changing stratagem that reduces emissions and fuel use that never really happens in real life driving.

I apologise for seeming cynical.
 

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My display shows 7
the S never changes on the display
 

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There are a few comments on this subject in various Mercedes blogs out of Germany.

The 7G box has 6th gear as the 1:1 with 7 as an overdrive with a .8 ratio. The 9G has added two more overdrive ratios of .7 and .6 purely for the sake of fuel economy and efficiency - which of course is what it is all about this day and age. Problem appears to be that some engines do not have the torque necessary to provide a smooth ride without the engine shaking all over the place. so MB put in electronic restrictions on the 9th gear to engage unless conditions are absolutely right. Bear in mind that an engine under stress at low RPM is more thirsty than a high revving engine with no stress, so MB must be very careful in allowing gear changes if all they are going to do is defeat the 'economy' object.

However, I would have thought the 300 engine would have the necessary torque especially in such a lightweight car, so maybe you should have a word with your dealer to see if there is such a restriction and if so, what are the 'right' conditions. If you are fortunate, the dealer might have a rolling road - ask to put the car onto it with zero resistance set and see if you can induce the change.
 

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However, I would have thought the 300 engine would have the necessary torque especially in such a lightweight car, so maybe you should have a word with your dealer to see if there is such a restriction and if so, what are the 'right' conditions. If you are fortunate, the dealer might have a rolling road - ask to put the car onto it with zero resistance set and see if you can induce the change.
With 370Nm torque available on the 300 from only 1500rpm I would agree, it should have enough to get into 9th but it's geared to 55mph/1000 rpm so it would only be pulling 3000rpm at its limited top speed of 250km/h. That's pretty ridiculous.
 

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* Founding Member #2
2008 SLK55 AMG
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My display shows 7
the S never changes on the display
IIRC, the newer instrument display shows the gear number as D1, D2 ...
In addition it displays the tranny mode: S (Sport), E (Economy) ....
 

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was referring to Bumpa2 post. he said 7 is never shown

http://www.slkworld.com/2657721-post5.html
He has a 2006 SLK55, IIRC the older instrument panel has a different AMG menu in the MFD as opposed to the later version, 2007 and later. The older one IIRC does not have the lap counter, etc.

Moreover, I don't know if he is using the AMG menu on the upper MFD or just looking at the gear numbers as displayed in the lower MFD.
 

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He has a 2006 SLK55, IIRC the older instrument panel has a different AMG menu in the MFD as opposed to the later version, 2007 and later. The older one IIRC does not have the lap counter, etc.

Moreover, I don't know if he is using the AMG menu on the upper MFD or just looking at the gear numbers as displayed in the lower MFD.
I'm talking about the gear numbers in the lower part of the MFD, I'm not sure what other part of it has gearing displayed.
 
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