Sent car back to dealer

[Y8cel]

Had my Slk55 a month now and when cold the gearbox drops from second to first with quite a jolt. What is the likely outcome of this I have read on various forums this is quite a widespread problem,
What experiences and solutions have other had with the same problem.
Car is a 2008 with 45k miles

Also the drivers rear window does not close properly and has cut the seal on the roof, my dealer said they keep this seal in stock saying to me this is a common problem.

Cheers

 

[davidjpowell]

they all do that sir.
software update
valve body (unlikely)

 

[Auto-mobile]

As above valvebody due to speed sensor fault.

 

[Y8cel]

Sorry to be thick could you elaborate so I can sound knowledgable to the dealer ta

 

[redbaron]

All 7g boxes bang from 2nd to first when cold.

 

[BlackC55]

Not all do. Just some.

Most are a software glitch or a valve body issue.

 

[Y8cel]

I refuse to believe they all do it and it's normal,

 

[redbaron]

Not all do. Just some.

Most are a software glitch or a valve body issue.

Olly respect your opinion and the later boxs may be better but drove lots and lots of 7g boxes when i was at merc main dealer and pretty much every one was much less smooth than 5g when cold.

Perhaps the OP's definition of an unsmooth change is different to mine.. Dont get me wrong im not talking robotised manual smg box in "smash it to bits" mode... just a hearty thunk / lurch.

 

[st4]

Olly respect your opinion and the later boxs may be better but drove lots and lots of 7g boxes when i was at merc main dealer and pretty much every one was much less smooth than 5g when cold.

Perhaps the OP's definition of an unsmooth change is different to mine.. Dont get me wrong im not talking robotised manual smg box in "smash it to bits" mode... just a hearty thunk / lurch.

7g is rubbish. Uselss.

Its something the OP will have to live with. They may cure the harsh downshift with a sofrware update but it will be at the expense of something else.I know. Mine didn't harshly downshift but flared violently on the 1 into 2 upshift and bucked from 3 into 4. Uselss. A learner can do better

Why. 7g boxes don't have sprag clutches which are there to dampen down harsh changes. Why is this, because they wanted to make the box fit into the 5g casing so it could be fitted to cars designed around 5g.

Its a rubbish box, always has been, always will be. Some get better ones than others but none are any good compared to a 5g car

 

[Y8cel]

Isn't mine a 7g+ 2008 facelift car?

 

[Dieselman]

Isn't mine a 7g+ 2008 facelift car?

Should be OK, but it is true that some do bang on the 2-1 downshift and have been incurable.

 

[st4]

Isn't mine a 7g+ 2008 facelift car?

No. Its a 7g. Sounds like everyone elses, rubbish

 

[st4]

Should be OK, but it is true that some do bang on the 2-1 downshift and have been incurable.

They bang on the 1 to 2 upshift (2 I've driven do this) and the 3 into 4 is lumpy.

 

[redbaron]

7g is rubbish. Uselss.

Its something the OP will have to live with. They may cure the harsh downshift with a sofrware update but it will be at the expense of something else.I know. Mine didn't harshly downshift but flared violently on the 1 into 2 upshift and bucked from 3 into 4. Uselss. A learner can do better

Why. 7g boxes don't have sprag clutches which are there to dampen down harsh changes. Why is this, because they wanted to make the box fit into the 5g casing so it could be fitted to cars designed around 5g.

Its a rubbish box, always has been, always will be. Some get better ones than others but none are any good compared to a 5g car

Top ranting...

 

[V12]

You guys want to take a trip in the old 124 I'm driving this week...that will make any 7g feel smooth!

 

[spanner]

124 should have lovely smooth shifts.

 

[Ian Donkin]

Our 80,000 mile R320CDI came with an £1,800 bill for a valve body just 300 miles previously and it is (not surprisingly) perfect. Our E320CDI has 128,000 miles on it and whilst not as good since it's last oil change, only rarely does it jerk at all between first and second. Both hold the vehicle on steep hills at a standstill and 'creep' like an auto should.

I've now had two 5g and two 7g Merc's and in my experience the 7g has been the better experience thus far.

 

[st4]

Top ranting...

More expressively worded facts

 

[Paul/]

I refuse to believe they all do it and it's normal,

If you search the last 3 or 4 months for 7g threads you'll see that some people have had bad experiences or negative opinions but many others are happy with the box. There's even a 7g Appreciation thread inspired by ***.

 

[st4]

If you search the last 3 or 4 months for 7g threads you'll see that some people have had bad experiences or negative opinions but many others are happy with the box. There's even a 7g Appreciation thread inspired by ***.

I think 7g is a blinder pulled by MB. Some say their cars lack character. Not fitted with 7g they don't. Some flare shifts, some shift badly, some shift ok according to drives, some need valve blocks at £1800 a pop, some don't, some improve with software fixes, some get worse.

The lottery makes them exciting and characterful, like an 80's Alfa. You know there will be issues, you don't know which ones:bannana::bannana::bannana: