W220 S320Cdi: Engine noice and gear change smoothness whilst cold?

[Paul S320CDi]

How noisy is a S320Cdi when cold? When accelerating mine is quite loud. It's a deep roar though rather than a tractor sound. When warm and cruising at a steady speed it's almost silent.

Also when cold the gear changes are not smooth. It goes with quite a surge. After a few minutes gear changes are very hard to detect.

Are these things normal? I guess if you were a chauffeur you'd have the car warm before you picked up your client anyway

 

[stumpy]

can't comment on the noise as mine is a 500 but the gearchanges on mine are smooth even when cold, but every now and again the 7 speeder thumps a gear.

 

[tromppost]

Has the gear box oil and filter been changed? Had mine done at the last service. 65.000 miles. it's like driving a new car.

 

[Paul S320CDi]

Has the gear box oil and filter been changed? Had mine done at the last service. 65.000 miles. it's like driving a new car.

I don't know. It has all the stamps in the book, so if it was scheduled to be done then I presume it has been. It's done 72k and ASSYST is showing 2800 miles to Service A.

I will probably get it done so I am sure. It's probably the cheapest option to start with.

Thanks

 

[Paul S320CDi]

every now and again the 7 speeder thumps a gear.

Even when you are driving nicely or just when you boot it?

 

[stumpy]

Even when you are driving nicely or just when you boot it?

Bit of both really. Happens so rarely that it is a shock when it does. Generally it seems to be when the gearbox and my foot get out of sync and it hesitates a bit.

 

[hawk20]

There is updated software for the seven speeder which has had problems with the odd rough shift (especially lower gears) right from the outset. Worth getting this attended to when next having an MB service as the update is, of course, free.

Same applies to other models with the 7 speed box. All been updated if lumpy changes.

But the 5 speed box on the 320cdi 220 series is as smooth as silk normally. Great box which I prefer to the 7 speed since a diesel has so much torque it does not need 7 gears IMO. Time to check that the ATF was changed at about 50k miles. May not have been as for a while MB were saying not necessary but many, many have found vast improvement after doing the change.

The straight six 3.2 litre engine in the 220 series is a bit noisy when cold but becomes peaceful once it is warm. Wonderful kick in the back when accelerating.

The V6 3.0 litre in 221 series is so quiet even when cold you would think it was a petrol engine. Less of a kick in the back partly because of the 7 speed box I think. Silky smooth though.