C350cdi feedback required

[Geoff A]

I have a 265hp C350cdi B/E sport estate on test for a week and would welcome owners of same car to share in my experiences of the following:
1) Driver's side of transmission tunnel gets hot. Is this normal behaviour? Heating was set at 20c throughout car, and used as single zone. Anyone else noticed this?
2) Radar for distronic plus decided to throw a fault. Though it reset automatically after about half an hour. Common issue? Can this be reset to standard cruise as i hate the interference of distronic plus.
3) Lots of road noise from 18in M+S tyres that Merc has fitted to test vehicles. Are standard tyres quieter? (i do not want a debate on temperatures and the weather)
Thanks for any feedback, Geoff

 

[This is Pete]

From experience of my E class, I usually rest my leg against the transmission tunnel and haven't ever noticed and warmth.

I get a fair bit of road noise from the tires (35 profile on the rears) but after a few weeks ownership, I just don't notice it any more.

And yes, you can disable distronic (and all of the other driver aids as well).

 

[ace571]

Hi Geoff

I have the same car as you are testing. Never experienced the hot tunnel - will check next time I drive it.
Distronic is an optional extra, so don't spec it if standard cruise is enough.
Tyre noise - some certainly there, but then in 18" wide low profile rubber on sports suspension I would expect it to be. It can be spec's with 17" wheels as a NCO.

A really good car, I would certainly recommend it after having mine for 7 weeks.

 

[Geoff A]

Thanks guys. I think the distronic plus was knocked out automatically on the M6 as we passed by the area of jodrell bank (handbook says radio waves from telescopes can cause this).
And i'm so far enjoying the car immensely. Sunglasses holder in headlining is a poor idea and the pano-roof eats into headroom imo. But its a lovely place to sit.
Long term view is to replace my C270cdi in the rear future with a nearly-new C350cdi estate.

 

[developer]

Thanks guys. I think the distronic plus was knocked out automatically on the M6 as we passed by the area of jodrell bank (handbook says radio waves from telescopes can cause this).
And i'm so far enjoying the car immensely. Sunglasses holder in headlining is a poor idea and the pano-roof eats into headroom imo. But its a lovely place to sit.
Long term view is to replace my C270cdi in the rear future with a nearly-new C350cdi estate.

Persevere with Distronic - it's great once you've mastered it and, as above, you can turn it off.

 

[ace571]

Sunglasses holder in headlining is a poor idea and the pano-roof eats into headroom imo.

Pano definitely restricts headroom. It has to given its design.
What don't you like about the SG holder?

 

[texasjohn]

I found a lot of tyre noise on a C350 Sport with 18s too. C250 elegance on 17s was much better

 

[@MARK]

I have the same car

Noise - Yes. Indeed when I first picked the car up I was surprised how much more noise there was compared to the previous but this is tyre noise and tyre choice will make a big difference.

Heat - I have not noticed any excess heat anywhere

 

[Geoff A]

What don't you like about the SG holder?

I've smacked my head on it twice, as it sticks out that little bit too far.... Doh.

 

[Frugal]

I've smacked my head on it twice, as it sticks out that little bit too far.... Doh.

Agreed - the SG holder seems pretty poorly designed and finished, I'd rather have the grab handle. As for tunnel heat, I've not noticed anything unusual albeit with a smaller engine bluck.

 

[Geoff A]

Persevere with Distronic - it's great once you've mastered it and, as above, you can turn it off.

No thanks, I've experienced it on lots of press cars and I much prefer standard cruise without interference. Yes, you can turn it off, but then as I understand it, you have no cruise at all. It's defo not for me.

The heat soak through the right-hand side of the trans tunnel last night coming home was unreal. My left leg was casseroled nicely after 1.5 hours at gas mark 8 - in summer, wearing shorts for example, won't be much fun and there a/c will be working overtime. I'll phone MB tomorrow and let them know. They can look into it.

Overall, it's a very smooth motor - and putting the 'box in S instead of E raises the game considerably. The throttle becomes a precision instrument and the shift points are raised, making the V6 really keen to go.

A few niggles aside - some of them spec-related - its a top motor. Would I consider the 250CDi? Probably, but I'm not desperate to trade grunt and refinement for maybe a few more real-worlds mpgs.

 

[This is Pete]

Good to see you're enjoying the performance side of the 350. You'll get even more fun by derestricting the rev range (long pull on the downshift paddle) - this keeps the revs high and you won't have to wait for the downshift on kickdown.

The response and power is a whole level above S mode.

 

[developer]

You'll get even more fun by derestricting the rev range (long pull on the downshift paddle) - this keeps the revs high and you won't have to wait for the downshift on kickdown.

The response and power is a whole level above S mode.

Can you explain this please Pete - I've not heard of this on the V6/7g motor?

What do you mean by long pull?

Has your box got an M button?

 

[ace571]

Can you explain this please Pete - I've not heard of this on the V6/7g motor?

What do you mean by long pull?

Has your box got an M button?

By doing what Pete suggests above you put the 'box into the lowest possible gear it will allow without overrevving the engine. Hence the response is instant - over and beyond S mode, which will sharpen the throttle and drop gears quicker, but will still by default be in a higher gear until it kicks down.

Hope that makes sense?

 

[This is Pete]

Yes, I have an M mode.

If you short click the downshift, you'll downshift once, basically moving into manual mode.

A long pull on the downshift keeps you in auto mode, but raises the shift point up near the redline and shifts down appropriately. Where auto mode (even in S mode) will try and keep the engine speed low, derestricting the rev range will keep the engine speed higher and give you a lot more in the way of throttle response/power.

Particularly good for exits of roundabouts, slip roads, and overtaking.

A long pull on the upshift returns auto mode to the same mode as before.

I guess that M mode would do the same, but can lead you into being in too high a gear for the engine speed and forcing you into manually downshifting to get back into the power band.


I tend to use this mode when I know up ahead that I'll need a good throttle response as the standard auto modes can leave you bogged down if you take it by surprise.

Hope I've explained that ok.

 

[developer]

The only bit I can't get my brain around is the difference between downshifting with the paddle and a long pull on the paddle, which you seem to be indicating is something different.

On mine, a downshift always drops to the correct gear to match the revs your're applying with the throttle.

So, if you paddle down and give it the beans it will drop from (for example) 7th to 3rd and away you go. I'm not aware that holding the paddle for longer does anything different.

However, your engines are newer than mine, so perhaps they are different .

 

[Colin_b]

After 9 hours driving my W204 320cdi yesterday I didn't notice any heat from the transmission tunnel at all...

 

[This is Pete]

Basically, a single click on the paddle will drop one gear, not necessarily the optimal gear for the engine speed.

 

[Geoff A]

After 9 hours driving my W204 320cdi yesterday I didn't notice any heat from the transmission tunnel at all...

Thanks for this. Unless its a specific trait of the latest C350cdi model, there could be something not quite right with this particular car.

 

[@MARK]

Basically, a single click on the paddle will drop one gear, not necessarily the optimal gear for the engine speed.

In fact it will put the car into Restricted Shift Mode.

Holding the paddle will also put it into Restricted Shift Mode but will keep changing down until such a point that changing down any more will damage the engine.

Once you have done this, the reason it revs to the top before changing is that you have told it not to change up but according to the manual

If the maximum engine speed for the shift range is reached and you continue to accelerate, the automatic transmission shifts up in order to prevent the engine from overrevving, even if the shift range is restricted.

So this is actually a feature to stop you blowing up the engine. It's not designed to do what you are doing with it