W221 2007 S320L CDI Kickdown Problem

[Hamodi]

Hi everyone,

I own a W221 2007 S320L CDI with 58,000 miles. It has a problem where 80% of the time when you kickdown it will feel like you hit a brick wall just before it should upshift (4000rpm). I have to lift my foot off the accelerator for it to shift up. If I keep my foot on the accelerator then it will do this violent kangaroo jerk jerk jerk and won't upshift.

This usually happens when kick down from standstill so gear change 1st-2nd. Or I could be driving in 3rd and kick down to 1st and same thing happens when it's about to shift to 2nd.

Done some searching and possible solutions may be gearbox oil and filter change or even the fuel filter? It's regularly been serviced with oil and filter changes but I don't see any record or gearbox oil or fuel filter.

But the posts I've read the 7G Tronic 722.9 issues are not matching my kick down symptoms and more to do with jerky gear change or when coming to a stop.

Anyone experienced the same symptoms? Thank you.

 

[Hamodi]

Just to add - if I drive it normally without kick down then it shifts normally at the correct RPM without jerking. It's just annoying because when I need it go fast it won't as I have to keep lifting off the accelerator to get it to shift!

 

[whitefang]

hi hamodi,
my dad had a merc few yrs ago, e class, auto. he still as merc now , a e220 cdi 170+bhp w211 & e300 td 225+bhp w210. he had the same thing, jerky box, he changed the oil on it & the little filter thing. & was ok, & he swears by the merc amg auto box.
il be talking to him tomorrow, if i remember il ask him what the oil he used & filter.
later mate.

 

[zipdip]

Welcome Hamodi ,when I started to read your post it seemed you thought the S320 was a F1 car,but I suppose owners can drive their cars as they want,I take it you are always in S mode,and so the car starts in 1st,have you tried running it in C ,and maybe run it in manual to see if the problem is still there,at 58,000 miles the box should not have had a oil and filter change,but this may well help,you do not say if you use a indy or main dealer to service the car,make sure you get the oil change done properly.

 

[Hamodi]

Whitefang - That's good to hear! Thank you very much.

Zipdip - Haha sorry, yes, I can see how it can be interpreted that way. Let me be clear and say I rarely use kick down (maybe once per week?). I mostly use the car for the London commute so isn't treated like an F1 car at all . What I meant was 80% of the time that I use it, the problem will occur - I now avoid using it even when needed as it feels like I slammed the brakes when it's supposed to shift up then start jerking if I don't lift off the accelerator. I'm sure you appreciate kick down can be useful sometimes. I actually always have it in C mode for my commute but have found it still happens in S and M mode after testing a few times.

Bought the car just under 2 year ago with 40k miles and FSH main dealer. I have the oil and oil filter changed at an indy every 5-10k using Castrol Edge 5W40 Low Ash as per previous service records. I changed the air filters and fuel filter myself yesterday with OEM parts - fuel filter had never been done and air filter last changed at 27k. Page 47 of my service booklet says Automatic transmission oil change 'Service 20 once at 40,000 miles (60,000 km)' and it includes the S class with 7-speed automatic transmission. I would say this is the only service item that my vehicle is not up to date with so I might start there, been getting some quotes at indys which are around £300.

Might take the EGR out later today for a clean. I wonder what it's condition will be after only 58k. Thanks!

 

[whitefang]

Hi mate.
Was talking to our dad, he said he used ... Atf134. 236.14 red. Gear box oil, he also changed the filter but he can't find the info on it, he as it somewhere in his book, if he finds it he'l buzz me then I can reply. But he said it sorted him out, think he said e300 td as 1 of the 1st amg auto box on. Hope this helps. Talk you soon.

 

[whitefang]

Hi mate.
Was talking to our dad, he said he used ... Atf134. 236.14 red. Gear box oil, he also changed the filter but he can't find the info on it, he as it somewhere in his book, if he finds it he'l buzz me then I can reply. But he said it sorted him out, think he said e300 td as 1 of the 1st amg auto box on. Hope this helps. Talk you soon.

 

[Hamodi]

Hi Whitefang, thank you very much. I just checked my manual and it says my automatic transmission 722.9 7G Tronic is using ATF 236.14 red.

 

[whitefang]

meant to be the best oil for that unit.

i put a thread (started 1) the other day, & was looking over other people's seeing what they was saying, & i just noticed that you said 722.9, that just reminded me about the time we (dad & i helped) change his auto oil.
nice to be thanked some times, thank you.
talk to you soon mate. good luck with it.

 

[Hamodi]

UPDATE

Had the automatic gearbox serviced today at a Mercedes Specialist. Oil was old/dirty but no metal bits to indicate any unusual wear. Car shifts much more smoothly now especially in gears 1-3. However, problem persists. Still jerks violently/kangarooing almost always when on full throttle around 3000rpm+.

Indy said there are 4 engine codes indicating turbo issue - car has only done 59k so I said I'd have a look. I've just taken the pin off the actuator to separate the lever from the turbo. The lever does move the full range without much force but I can definitely feel it snagging - could be stuck VNT?

Any easy way to free up the vanes or must I remove the entire turbo? I tried removing an 18mm bolt on the top of the turbo but I just see some oil inside? I was going to remove the 3x 10mm exhaust bolts but unfortunately it seems one of them is worn. Not sure whether to persist on reaching the vanes to clean, or just deciding whether this minimal snagging is normal and perhaps I should be looking at the actuator?

Any advice on OM642 VNT cleaning or normal lever movement? Thank you!

 

[W221copea]

As i understand MB consider the box to be a sealed unit and only perform one time fluid change early in teh cars life to remove any "wearing in" debris from the box. I have a delayed shit into 6/7 and had MB perform a service on the box and also update the software at a cost of ~£300. The issue is resolved.

BTW - my car is on 158K, initial lube on box was 36K and the one i requested was at ~150K