smjc_99

I am conisdering the SLK 55 AMG and may trade in my 2002 M3 smg.

I heard that the manual shifting in M mode is not always executed by the tranny.

Like when your are in 4th gear at 35-40 , can you pull the left paddle quickly twice to dwonshift to 2?

OR do you have to click once to change to 3 and then click again?

Also when you downshift from a higher gear to a lower gear and if the lower gear is within the RPM range for that lower gear will the shift always happen OR is it sometimes ignored by the TRANSmISIIOn and why ?

Also, Are the Revs matched by the Transmission during downshifting?

The 07 Brochure says it does Rev match on the 7 speed?

Any opinions will be greatly appreciated as M mode is what I will be using most of the time

Thanks

Shark

No, in the example you used, clicking the downshift paddle the second time won't do anything unless the 4-3 downshift has already been completed. I wish it was the way you described, but it's not. And revs are not matched. I drive my '55 in M mode 95% of the time, and while I enjoy doing my own shifting sometimes you cannot immediately get the gear you want. Aside from these issues, both the upshifts and downshifts are very quick for a traditional automatic trans.

smjc_99

Thaks Shark,
I guess it could be furstrating that when you wanna downshift say from 5th to 3rd , one had to pull the paddle ad have the trans downshift to 4th and thn pull again to go the 3rd gear

Also I am not sure why the trans ignore downshifts sometimes when the RPM for the downshift is acceptable

Looks like M mode is not that great. I hope I can get more feedback before I make the decision whether to get 55 AMG auto or SLk 350 6 speed

SLK55R

I don't use the M mode unless I'm in the hills and I want to keep the tranny from upshifting to another gear that I dont want. For example I don't want the tranny to go up to 5th gear. They I have M mode into 4th. In the hills I usually am in 3rd or 4th.

Other than that I don't use M mode at all. I find the auto S mode to be faster at downshifting than M mode. What you do need to do though is reset your ECU and do some hard driving so that the S mode keeps the car in higher revs.

slk55er

I agree with SLK55R -- forget the manual mode. I have not really found a use for it yet. It even downshifts into 1st when stopped, even if you've selected 2nd, thus precluding a 2nd gear stat as you might want on snow, for example.

However, S Mode works great on the track and, unless the resulting engine rpm would be too high, it WILL allow downshifting directly through to a several gears lower.

For example, if you are approaching a turn in 4th and need 2nd gear for a rapid exit (slow in, fast out), two rapid clicks while braking hard can result in bypassing 3rd gear completely and going directly into 2nd (or even 1st with 3 clicks.) You may have to practice this a bit 'cause if you double click at too high an rpm, 2nd gear could result in over revving the engine and the ECU will not allow that.

Other than the M mode operation, I could not be more pleased with this transmission.

smjc_99

55Er, Thanks for your response on the S mode

I didnt know that you can change gears in S mode through the paddles

What is the real diff between the S mode and M mode

is it that M mode does not upshift ar redline?

Shinigami

That's pretty much it, i.e. in M mode, you have a bit more control.

It will not be as rapid as an M3 with SMG, but it will do a small rev blip if you keep the pedal down when you shift down gears, but being an automatic, it is not fast.

Although a gear change itself is quite quick, it sometimes takes time while the box figures out when the safest moment to do so comes around.

Maybe the newest models are quicker, because when I drove an E63 AMG, downshifts as well as upshifts were much quicker then in my SLK 55 AMG. Possibly because of software updates (my SLK is now 2 years old, whilst the E63 was built 2-3 months ago... so it has some updates throughout).

Leave it on S, and when you feel like playing around, flip the paddles/buttons and you can play around with leaving the car in one gear. It's fun in that you can open up the engine melodies. I really like to make the engine sing as 2, 3 and 4th gear at 3-4000rpm when city driving.

smjc_99

so looks like downshifting when coming to a stop light will be jerky since rev matchng may not happen since I wont be firm on the acc pedal when comng to a light

I will test drive and see if the manual mode really sucks

Not sure if the 2007 SLk 55 AMG has any update on the trans software

Shark

Downshifts while slowing for a traffic light are not that jerky, no more than most other traditional automatic transmissions. The one exception is the 2-1 downshift. And mine was extremely harsh last winter when the trans was cold until the dealer upgraded the trans software.

Addicted2Speed

I used to have an e46 m3 with SMG too, and unfortunately, the automatic is nothing like it. Even in higher end cars like porsche turbo's, the auto transmission is slow and unresponsive. I think it is downright idiotic that car brands like Mercedes and Porsche don't have real F1-style transmissions in their high end cars, when BMW (smg) and Audi (dsg) do. Its really the only thing that keeps Mercedes from being "perfect" in my view...