'02 C240 - high RPMs at Highway Speeds
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2002 C240
'02 C240 - high RPMs at Highway Speeds
I have a '02 C240 w/ ~200k miles, AT. I have recently noticed that at highway speeds (>50MPH) the RPMs seems higher than normal & under normal acceleration on highway once I take my foot off the gas the car slows down quickly (10 MPH in a couple seconds). Here are some RPMs/speeds
60 MPH - 2700 RPM
70 MPH - 3000 RPM
80 MPH - 3300 RPM
I have had it looked at by the dealership twice & they said it shifts fine. Are these typical numbers for this car? I am always in the 'D' don't use the manual shifting mode.
Thanks in advance
Andy
60 MPH - 2700 RPM
70 MPH - 3000 RPM
80 MPH - 3300 RPM
I have had it looked at by the dealership twice & they said it shifts fine. Are these typical numbers for this car? I am always in the 'D' don't use the manual shifting mode.
Thanks in advance
Andy
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2002 C240
I'd appreciate it if you both would test & let me know. I did another road test & had it at about 60MPH in the manual 4 gear & then shifted it to 'D' & it did shift fine. It just feels like it is running at higher RPMs & does not coast at all.
I am not much of a car guy, just trying to either accept the dealer's suggestion that its fine or get more info on what to have checked.
Thanks
Andy
I am not much of a car guy, just trying to either accept the dealer's suggestion that its fine or get more info on what to have checked.
Thanks
Andy
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From: Sacramento/San Gabriel/Riverside
01' C32o
Mine is weird, at 80, depending on things, I've had it at 3200rpm, and at other times, at 3000 flat. But I think, from my experience, it always changes when I reset the throttle. After a week or so, it would adapt to my driving style.
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MBWorld Fanatic!
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From: Sacramento/San Gabriel/Riverside
01' C32o
That's what I thought too. But this occurred when I had my Brabus reps on. It would change whenever I did a throttle reset, no lie. It was something that kept on bugging me too. Maybe my tach is f cking up.
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From: Nor Cal
A Car
I think our engines rev noticably high at highway speeds compaired to others. I know Hondas [with 5 speed autos] cruising ~80mph barely gets up to 3k rpm like ours. This obviously isnt a problem for newer MB's anymore as they are now using the 7G tranny.
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Joined: May 2007
Posts: 93
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From: Chicago
08 E350 4MATIC
At 70MPH in 5th, my engine spins right at 3,000 RPM.
I've noticed my fuel usage starts to noticeably increase above 3,000 RPM,
but boy is she happy to purr that fast (and above) for hours and hours!
I make frequent 300 mile interstate trips (1 way) and have never been more
pleased with a vehicle's driving performance. Electronics OTOH, not so much.
Happy driving...
I've noticed my fuel usage starts to noticeably increase above 3,000 RPM,
but boy is she happy to purr that fast (and above) for hours and hours!
I make frequent 300 mile interstate trips (1 way) and have never been more
pleased with a vehicle's driving performance. Electronics OTOH, not so much.
Happy driving...
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2016 GLE 350
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Confirm correct & slows down because the torque converter is locked up so you are running against compression - no coasting. This is correct.
Mu - you might be seeing this because of your glycol problem & the tranny misbehaving.
Mu - you might be seeing this because of your glycol problem & the tranny misbehaving.
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2002 C240
Thanks to all for the replies. I am glad to see these are normal numbers. Not sure why after 7 years I am just noticing it, but I'll chalk that up to an operator issue.
Glyn, can you explain more why the torque converter would be the explanation for no coasting. I am not a car guy, so this maybe basic knowledge for others.
Andy
Glyn, can you explain more why the torque converter would be the explanation for no coasting. I am not a car guy, so this maybe basic knowledge for others.
Andy
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Sure - Old auto boxes had the engine coupled to the auto gearbox via a torque converter (think American - GM Trimatic or Chrysler Torqueflight). These fluid flywheels allowed large amounts of slip for smoothness & the GBs had crude hydraulic control. When you lifted off the gas the car virtually freewheeled so you had little or no braking effect from the engine because there was no direct lock up between it & the transmission. This set up was smooth (slush box) but hopelessly inefficient with huge power loss (energy loss) through the transmission mainly due to TC slip.
Modern electronically controlled Auto boxes like your car has, have a set of lock up clutches on the torque converter which are locked up from just after pull away until just before you stop. So the engine is direct coupled to the transmission similar to a manual car. This is comparatively efficient as there is no longer any slip via the torque converter.
So when you lift off the throttle you are running against full engine compression just like a manual car and will slow down due the braking effect of the engine.
Hope I have explained clearly enough.
Modern electronically controlled Auto boxes like your car has, have a set of lock up clutches on the torque converter which are locked up from just after pull away until just before you stop. So the engine is direct coupled to the transmission similar to a manual car. This is comparatively efficient as there is no longer any slip via the torque converter.
So when you lift off the throttle you are running against full engine compression just like a manual car and will slow down due the braking effect of the engine.
Hope I have explained clearly enough.
Last edited by Glyn M Ruck; Dec 10, 2009 at 12:46 PM. Reason: typo
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From: BC, Canada
2003 C230K Coupe Orion Blue
My 2003 C230 gets 3000 @ 120km/h, which is exactly 70kph. Sounds normal.
What they should've done imo is gotten rid of that stupid S/W switch and made 1st gear S the same ratio as our current 1st gear W. I think I've used that 1S gear maybe 20 times since I bought the car, to impress friends in a parking lot. That gear is so short it's useless.
What they should've done imo is gotten rid of that stupid S/W switch and made 1st gear S the same ratio as our current 1st gear W. I think I've used that 1S gear maybe 20 times since I bought the car, to impress friends in a parking lot. That gear is so short it's useless.
Last edited by slammer111; Dec 10, 2009 at 05:02 PM.
MBWorld Fanatic!
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From: BC, Canada
2003 C230K Coupe Orion Blue
^ Yeah, for 2002-2003 it's Summer/Winter, and for 2004+ it's Sport/Comfort. We have the exact same button with different lettering. 1st gear is so useless on this car. They could've made our current 2nd gears the real 1st gear, so that our 5th gear would have much lower RPM on the highway.
Of course this can be easily done with a rear differential mod, but the cost would outweigh the savings unless you drove on highways regularly.
Does anybody here use S regularly in their W203?
Of course this can be easily done with a rear differential mod, but the cost would outweigh the savings unless you drove on highways regularly.
Does anybody here use S regularly in their W203?
Last edited by slammer111; Dec 10, 2009 at 04:50 PM.
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2019 G70 6MT & 2022 Ford Maverick XL
Okay I knew that the pre-2004 cars had S/W instead of S/C, but I didn't know the function was different. I always use S mode in my C230, starting off in 1st and shifting through all 5 gears. At WOT, 1st gear seems short. Or am I misunderstanding this?
MBWorld Fanatic!
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From: BC, Canada
2003 C230K Coupe Orion Blue
No, the functions are identical. 
They just changed the lettering on the button.
Shorter gear = higher revs at a given speed. Therefore, the 1st gear is stupidly shortfor this car.
I've never understood why car manufacturers didn't just spread out the gear ratios more to improve fuel efficiency. Most cars cruise at much higher RPMs than needed. Nobody needs 3000rpm if you're not passing anyone; that's what downshifting is for. They finally got it right with 7G-Tronic.
They just changed the lettering on the button.Shorter gear = higher revs at a given speed. Therefore, the 1st gear is stupidly shortfor this car.
I've never understood why car manufacturers didn't just spread out the gear ratios more to improve fuel efficiency. Most cars cruise at much higher RPMs than needed. Nobody needs 3000rpm if you're not passing anyone; that's what downshifting is for. They finally got it right with 7G-Tronic.
Last edited by slammer111; Dec 10, 2009 at 05:02 PM.
