Transmission Mode C or S?
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From: United States
2008 R350 & 2008 C300
Transmission Mode C or S?
Just been doing some reading up on the transmission modes. S or standard and C or comfort. C starts out in second gear and is good for winter driving, but not only that, it shifts sooner resulting in a smoother shift pattern. The standard mode starts in first gear and holds the gears longer. Also of note under the break in period section it states that for the first 1000 miles the car should be driven in C mode only. The main question here is what mode to you leave your transmission in and if you have played with both modes, do they effect gas mileage? Comfort mode shifting quicker and getting the transmission in a higher gear without higher revs would improve gas mileage I would think? Just throwing this out there haven't read much about it on here.
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From: Seattle
C-300, XC70, Wrangler
Making it go "thunk!"
I keep mine in S, standard mode. I rarely use "C" ... just my approach.
But, I can make that tranny go "thunk!" It's easy. Get into a situation in traffic where you are braking then accelerating, then braking and so on. A quick hard brake followed very quickly with accelerating makes that tranny thunk.
Not a nice sound.
Another place where it is sub-optimal is when you accelerate hard, reach revs above 4,500 rpm, and then level out. It doesn't shift to a higher gear, but it just sits there in current gear, kind of flattening out. Even letting up on the gas doesn't make it shift. (Takes a while to decide, finally, it's done accelerating.)
Yikes, what am I doing to this car?
My last two Hondas (yeah, Accords with VTEC engines) had plenty of run-it-to-redline activity. Both lasted well over standard trade in (100K miles), and both were running strong when replaced (one was stolen, the other traded for the C). I don't run the C to redline much at all. This tranny is too quick to shift unless I really put my foot in it, and when I do that, I'm well over any reasonable speed limit ;-)
Oh well. MB makes good strong engines, right?
Oh, about gas mileage. C300, 7-spd. Tank average is staying at about 26.5 or so with 5300 miles on it. On the freeway, it can reach 30.x mpg before I have to get off and do city streets again. All in S. No C data to compare (I didn't read that part of the manual, so skipped the first 1K miles in C, but I didn't run it hard then.)
But, I can make that tranny go "thunk!" It's easy. Get into a situation in traffic where you are braking then accelerating, then braking and so on. A quick hard brake followed very quickly with accelerating makes that tranny thunk.
Not a nice sound.
Another place where it is sub-optimal is when you accelerate hard, reach revs above 4,500 rpm, and then level out. It doesn't shift to a higher gear, but it just sits there in current gear, kind of flattening out. Even letting up on the gas doesn't make it shift. (Takes a while to decide, finally, it's done accelerating.)
Yikes, what am I doing to this car?
My last two Hondas (yeah, Accords with VTEC engines) had plenty of run-it-to-redline activity. Both lasted well over standard trade in (100K miles), and both were running strong when replaced (one was stolen, the other traded for the C). I don't run the C to redline much at all. This tranny is too quick to shift unless I really put my foot in it, and when I do that, I'm well over any reasonable speed limit ;-)
Oh well. MB makes good strong engines, right?
Oh, about gas mileage. C300, 7-spd. Tank average is staying at about 26.5 or so with 5300 miles on it. On the freeway, it can reach 30.x mpg before I have to get off and do city streets again. All in S. No C data to compare (I didn't read that part of the manual, so skipped the first 1K miles in C, but I didn't run it hard then.)
Last edited by jstaneff; Mar 4, 2008 at 12:46 AM.
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As far as I heard, this is a common 7 G-Tronic gearbox fault. Have it checked. I think they need to replace a part attached to the torque converter.
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From: SFV CA
2008 Black Out C350 Saks Edition / 87 VW GTI
There is a few threads post in the past about comfort and sport mode settings.
Personally I keep my in "C" mode, I notice I get about 35 more miles per tank, I do mostly all my driving on the streets and I like the smooth shifting.
Personally I keep my in "C" mode, I notice I get about 35 more miles per tank, I do mostly all my driving on the streets and I like the smooth shifting.
Last edited by tanktube67; Mar 4, 2008 at 09:28 AM.
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C300
I noticed that most of time "S" runs in 1 gear lower than "C" mode at any speed except 70mph or faster. in "C", 7th gear kick in around 60mph. in "S" 7th gear kick in around 70mph
This means "S" mode runs in higer PRM than "C" mode most of time which definatly eats more gas. IMO
This means "S" mode runs in higer PRM than "C" mode most of time which definatly eats more gas. IMO
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From: Seattle
C-300, XC70, Wrangler
That's an interesting observation about S vrs C and rpms. One study I've been looking at (to assign to engineering students [I teach in a college]) is that it's not the rpms, but the torque used. Running at about 80% of the peak torque, in whatever gear is appropriate for the speed you're driving, is the correct stance with respect to better mileage.
The intuitive idea that higher rpms means it drinks more gas is not true, even if it seems counter intuitive. In some situations, being at a low rpm in too high a gear is very bad for mileage since it's much harder to accelerate. (That's called lugging.)
The intuitive idea that higher rpms means it drinks more gas is not true, even if it seems counter intuitive. In some situations, being at a low rpm in too high a gear is very bad for mileage since it's much harder to accelerate. (That's called lugging.)
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C300
That's an interesting observation about S vrs C and rpms. One study I've been looking at (to assign to engineering students [I teach in a college]) is that it's not the rpms, but the torque used. Running at about 80% of the peak torque, in whatever gear is appropriate for the speed you're driving, is the correct stance with respect to better mileage.
The intuitive idea that higher rpms means it drinks more gas is not true, even if it seems counter intuitive. In some situations, being at a low rpm in too high a gear is very bad for mileage since it's much harder to accelerate. (That's called lugging.)
The intuitive idea that higher rpms means it drinks more gas is not true, even if it seems counter intuitive. In some situations, being at a low rpm in too high a gear is very bad for mileage since it's much harder to accelerate. (That's called lugging.)
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Thread Starter
MBWorld Fanatic!
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From: United States
2008 R350 & 2008 C300
All good information. The only reason I ask this is because in the past salesmen have always told me to keep the transmission in S mode unless I were to be taking off in winter conditions. I just picked up a new 08 R class and the salesman was telling me about the transmission setup and said for daily driving C or comfort mode was best suited. This went against what I had always been told so I got out the book and did some reading and sure enough it recommends C mode as well for daily driving. I'm sure the R and C transmissions are different in their programming, so the bigger heavier R class would probably shift better with the C mode than a C class in C mode, but I think I'll try it out. I do experience some hard shifts from time to time in the C, this could remedy it, just hope it doesn't rob me off too much umph..cause you all know we need all the umph we can get in the C300. ha ha ha
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From: West Michigan
2007 E63
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From: Silicon Valley, CA
1999 C280 Previous / 2008 E350
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From: Turkiye
Waiting for W204 Facelift
very good thread
this is very good issue about mercedes cars ! I am always confused since I got W203
past mercedes cars had W instead of C and asked them what means W ? They said W means Winter and S is summer that in Winter mode engine pass second gear and S is first...
with new models S is called Sport mode that tough suspansion and C is called Comfort mode smooth suspansion but I am not experienced driver and never too much feel difference two modes
and gas usage I did not see much difference too much
I use mostly C mode and it seems to me OK !
I think this diffence -maybe % 0.1 - that normal drivers could not feel much
here quote ; for active safety reasons using S mode in highway ? maybe tough suspansion but this is not means in c mode we are danger !
I think this is a commercial game to me
