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jimmy

MB Enthusiast
Joined
Aug 8, 2002
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2,316
Location
Northamptonshire
Car
Discovery 3 TDV6, Discovery 300TDi - Plaything!
Some advice please. I am new to driving an automatic and as I dont yet have a handbook, I thought some of you could offer some advice.

When I am sat in slow/stationary traffic, I knock the car into 'N'eutral so as to prevent the car trying to pull whilst held on the brakes. Is this a good idea or totally uneccessary?

My C180 has the five speed auto box, not the 'tip-tronic' version. When wanting to overtake is it OK to knock it down to 4 or even 3 manually in order to overtake quicker? It just seems quicker than waiting for the kickdown if you can see an opportunity to go.

I know the W and S button is for winter and summer driving, but I have tried it in W and cannot tell much if any difference in the gear changes. Isnt it supposed to pull off in 2nd and change gear sooner, or is there no noticable difference?

Thanks.
 
Hi Jimmy,

this is simply from experience and what I've heard....hopefully others will correct me if I'm wrong !

1. I must admit, I've started dropping into nuetral occassionally when stationary for lenghty periods etc.  I can't see as keeping it in D will make too much difference in everyday driving conditions though.  However, I've heard that holding the brakes on after extreme usage can encourage heat-sink and possibly lead to warped discs <img src="http://www.mbclub.co.uk/iB_html/non-cgi/emoticons/wow.gif" border="0" valign="absmiddle" alt=':0'> (and we all know how delicate W202 discs can be).

2. Can't say I've noticed any speed advantage to manual changes over the kickdown.  Remember the box is electronically controlled and adjusts its performance to match your driving style.   Must say though it's nice once in a while to use the box manually and have some fun.  Oh yeah, I drove a service manager's tiptronic C200 for about 3 weeks last year (long story - don't ask) and didn't notice too much difference there either.

3. When switched to W your box will start off in 2nd every time to avoid wheelspin in slippery conditions etc.  The box will also change up to a higher gear quicker and do everything it can to hold the higher gear...until you hammer it with the kickdown.  This all adds to a more economical drive, or so I'm told.  If you select S then the box will start in 1st and hold onto a gear for longer (under acceleration) before changing up, thus maximising performance.

Hope this helps.
 
Dave is right.

Although im not too sure about manually dropping the box - I used to do that alot but I've now refrained myself from doing so <img src="http://www.mbclub.co.uk/iB_html/non-cgi/emoticons/sad.gif" border="0" valign="absmiddle" alt=':('>

Oh I only have a 4 Speed auto box and my settings are 'E' and 'S' for Economy or Sport.
 
I personally think the 5 speed electronic auto is great. &nbsp;I can't comment for the C180, but on my C230k when I bury the gas pedal I often get double kickdown <img src="http://www.mbclub.co.uk/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'> &nbsp;I find that the auto box predicts fairly well what I want to do, and I've never felt the need to move the shifter for more performance, although I've knocked it into 4th or 3rd when I've wanted some &quot;engine braking&quot;.

W mode sucks though, it didn't help much at all last winter <img src="http://www.mbclub.co.uk/iB_html/non-cgi/emoticons/sad.gif" border="0" valign="absmiddle" alt=':('>
 
We should all be leaving the box in 3 when driving about in the town for safety. This will give the most control over the car.

Try it , i don't do it all the time , but , you are in a lot more control over the car.

The correct way at traffic lights if you are sitting your driving test is to slide it into N and then apply the parking brake, back into D and remove then parking brake to move away.
 
Yes, the C180 will do a double kickdown too when needed, perhaps I should just leave it to get on with it on it's own.

I agree that the electronic box does a great job at adapting to your driving style, very clever stuff!

have got to take mine back to the dealer in a few hours, there is a small, thumbprint sized area of top coat or lacquer that has bubbled up and burst like a blister <img src="http://www.mbclub.co.uk/iB_html/non-cgi/emoticons/confused.gif" border="0" valign="absmiddle" alt='???'> I am hoping they will put it right under warranty.

I shall try leaving it in third gear when I am driving through Leicester today........Leicester is great fun to drive through....NOT <img src="http://www.mbclub.co.uk/iB_html/non-cgi/emoticons/tounge.gif" border="0" valign="absmiddle" alt=':p'>
 
those with 5 speed auto's with the S &amp; W switch also have 2 reverse ratio's as the gearing is altered depending what position the switch is in.

This is supposed to assist you when rocking the car back and forth when stuck in mud or snow.
 
Just adding to this, if you have one of the older mercs like my 190 with the rather &quot;Lazy&quot; hydraulic gear box rather than the later electronic ones like yours, a manual shift down is essential quite a lot of the time, as you could boil an egg waiting for the kickdown sometimes!
 
A little tip for auto box boys...

If you are on say half throttle, and want to overtake, instead of pressing your foot right down (engaging kick-down) lift off and very quickly depress the accelorator again, you will find the car goes into super kickdown or double kickdown almost immediately.

On the elctronic box, the system they use is so precise that manually down shifting will prove no quicker than kick-down.

On thew old 190/124's etc... there are 2 kick-downs manuals kick-down (via cable) and electronic.

The electronic only kicks in on the double or super kick-down and the manual kick-down has some serious adjustment available...

One last point, Manually down-shifting is not reccomended by expert mercedes technicians...i did it in a E320CDI on a test drive, and got told off...

It should never be used if the kick-down system is set-up properly.
 
I agree with Shude's comments. I usually just leave mine in drive and the car pretty much knows what I want to do and when. In traffic I leave the car in 'D' and hold on the brakes. To add to Paul's comment... how many 'family saloons' out there have 2 reverse ratios in the gearbox <img src="http://www.mbclub.co.uk/iB_html/non-cgi/emoticons/wink.gif" border="0" valign="absmiddle" alt=';)'>

For those with the 5 speed electronic boxes, I'd also back up Andy Gayle's recommendation (MBOA board, until we can coax him here <img src="http://www.mbclub.co.uk/iB_html/non-cgi/emoticons/wink.gif" border="0" valign="absmiddle" alt=';)'> ) that if your car has done between 60k and 70k miles get the auto gearbox oil completely changed. MB party line is that they suggest that these boxes are sealed for life but most peoples' experience would suggest otherwise.I've just had mine done by George Fraser and my car drives much more responsively/smoothly than it did before, and it didn't particularly drive like a dog before either.

S.
 
I personally go into neutral and use the park brake at lights, although I do have my foot on the brake to show I'm stationary until a vehicle stops behind me. With modern high intensity brake lights, I feel it is impolite to dazzle a driver behind me, especially at night or if it's raining. I have also nudged someone in front of me when my foot pressure relaxed, hence the above!!
 

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