7G Tronic gearbox faults

[drfishfood]

Lots of you have been exceptionally generous and helped me with my gearbox problems. I would ask you another favour. Could you list any problems you have knowledge of that relate to the 7G Tronic garbox.

Simon Fernandez (Service Manager,Dealer, Milton Keynes) and Gary Morris (MB headquarters) tell me categorically that they have had "no problems" with this box. Mr Fernandez went on to state that in Sytner dealerships in Bedford and Northampton they also have no knowledge of any gearbox problems for the the 7G. It is only me who has problems!
I would dearly wish to prove them wrong

Bob

 

[moosehead]

2005 W203 C230 V6 with 7G - clunky / harsh downchanges. Several software upgrades over 3 year period. Eventually resolved approx 15 months ago.

Electro Hydraulic Control Unit failed at around 50K miles. Fortunately vehicle was in last month of warranty. The long term reliability of this box does concern me.

The vehicle always rolls back on hill regardless of whether it's in 'S' or 'C' mode. The dealer informed me that this was a feature of the 7G box. It can be a real pain as you need to use the handbrake or left foot on the brake. The wifes SLK with the 5 speed box doesn't do this.

The other strange thing it does in 'S' mode is if you pull up at some lights or a junction, just before you come to standstill you get a slight 'surge'. I'm not sure if this is the box dropping into 1st gear. It doesn't happen in 'C' mode. I've got to the point where I can't be bothered going back to the dealer for more updates / investigations.

 

[rich.g.williams]

bob,

maybe this business of other people having had problems is a bit of a "red herring"

at the end of the day you bought your car and its under warranty and should be 100% as intended by the manufacturer and to your satisfaction

if they are trying to say that you are imagining the problem get a friend or relative (or even AA inspection) who has experienced the problem to go along with you

 

[rich.g.williams]

moosehead,

historically autos always pulled in drive (especially with older engines where idle speed was not regulated)

however logically thinking:-

- its the engine that should provide power to drive the car (by way of pressing throttle)

- its the brake that should provide power to hold the car (by way of pressing footbrake)

 

[moosehead]

rich.g.williams

I understand your logic but this is the first auto that I have driven that rolls back on hills (even a slight incline). It wouldn't be so bad if the vehicle had a conventional handbrake but it really is a pain trying to negotiate a hill start with the foot brake and hand release. It's even worse when you are trying to manoeuvre the vehicle into say a tight parking space on an incline. I guess the plus side is when you are in traffic you can almost lift your foot off the brake and it won't creep forward.

 

[rich.g.williams]

personally I wouldn't bother using the Park brake for pulling off on hills, and I agree the foot operated Park brake is a big pain.

my method would be, left foot on main foot brake and right foot on accelerator, then press as little of both as needed to pull off on an incline smoothly and safely

after a bit of practice it becomes easy and second nature

 

[moosehead]

That's exactly what I do. Not really a major problem with hill starts but not so good when you are backwards and forwards into a parking space on an incline.

 

[Dosco]

Lots of you have been exceptionally generous and helped me with my gearbox problems. I would ask you another favour. Could you list any problems you have knowledge of that relate to the 7G Tronic garbox.

Simon Fernandez (Service Manager,Dealer, Milton Keynes) and Gary Morris (MB headquarters) tell me categorically that they have had "no problems" with this box. Mr Fernandez went on to state that in Sytner dealerships in Bedford and Northampton they also have no knowledge of any gearbox problems for the the 7G. It is only me who has problems!
I would dearly wish to prove them wrong

Bob

Hi Bob,

This guy is missing the point! You are having a problem and it needs resolving. Does he seriously think that by passing it off in such a way and seemingly treating you (the customer) with such disdain that's it and nothing more needs to be done or said?

I would arrange a meeting with him to go through this issue from top to bottom including a lengthy test drive and be sure to take someone with you ideally as a 'note taker' and 'witness' go through every detail and make sure his replies are noted accurately, offer to supply him a copy if he objects and if he still objects ask him why as you only want to ensure that what is said is accurately documented, no fair minded reasonable person could possibly object to that now could they!

You also need to 'request' the matter is escalated and you want the factory based technical team brought to bare on this matter in order to resolve the issue once and for all.

I would be a little cautious at quoting the experience of 'others' with the same/similar problems at this stage, its a bit like cold steel - they do not like it up 'em. By all means collect such info but keep your powder dry as they say.

I would, if you have not already done so, document everything you have done and had said to you so far just in case you have to go 'over the top' dates, times the what, when, how and who etc all of this is so important if you reach a total impasse.

Finally you can bet your bottom Dollar 'some one else' is also reading these posts so be aware

 

[Jlo]

Jlo

I've also had a problem with 7 g gearbox. From time to time it will not change down from 7th gear. Stopping the car and restarting seems to fix the problem temporarily. I brought this to the attention of Synter Newbury before the warranty expired ( and asked them to make a note on the service records ) and a software upgrade was made. It didn't solve the problem for long though. Now ( warranty expired ) they don't want to know. The problem is that if the car's diagnostics don't register a problem there appears to be nothing Synter can do. I'm now left with a large bill. Don't think I'll be buying another Merc in a hurry !

 

[Mic]

I've also had a problem with 7 g gearbox. From time to time it will not change down from 7th gear. Stopping the car and restarting seems to fix the problem temporarily. I brought this to the attention of Synter Newbury before the warranty expired ( and asked them to make a note on the service records ) and a software upgrade was made. It didn't solve the problem for long though. Now ( warranty expired ) they don't want to know. The problem is that if the car's diagnostics don't register a problem there appears to be nothing Synter can do. I'm now left with a large bill. Don't think I'll be buying another Merc in a hurry !

I would be pursuing this issue with considerable vigour and I would not expect to be bearing the costs of a permanent and satisfactory repair. Even if the problem had manifested itself out of warranty you should be able to expect some goodwill but given that you have registered the problem whilst the car was under warranty you should be able to expect satisfaction at MB's expense.
Don't let the b'tards beat you.

Hello and welcome.

Mic

 

[television]

I've also had a problem with 7 g gearbox. From time to time it will not change down from 7th gear. Stopping the car and restarting seems to fix the problem temporarily. I brought this to the attention of Synter Newbury before the warranty expired ( and asked them to make a note on the service records ) and a software upgrade was made. It didn't solve the problem for long though. Now ( warranty expired ) they don't want to know. The problem is that if the car's diagnostics don't register a problem there appears to be nothing Synter can do. I'm now left with a large bill. Don't think I'll be buying another Merc in a hurry !

As Mic,, you can insist that they fix it, it is something that they failed to do while under warranty

 

[topliner]

7G Gearbox problems

I've been having problems with the gearbox on my car and have posted several times and have received invaluable help/advice from members on this forum.
My car is back at the dealers again with gearshift problems although the car is out of warranty it went in while in warranty. It has had several re-adaptions a new valve body after which it drove fine for about three weeks before the gremlins returned. I got a call saying that there was nothing wrong with the gearbox although it is whinning and this has been put down to a pulley bearing which I find difficult to believe as it only whines when the car is being driven, when stationary and in neutral or park with engine running there is no whine even when revved. I feel that now the car is out of warranty I'm getting fobbed off, but as mentioned in a previous post by a member they have to fix the fault as it was not repaired while under warranty.
I am reluctant to get in touch with MB customer services as the service manager has I believe, tried to help but has also said that it would be a black mark against them and they would rather try and sort the problem out. The "nothing wrong" conclusion was that of the dealerships "senior" technician ( who can't even find why the steering wheel clunks when turned)and this he arrived at because the diagnostics show no fault codes, I reminded him that according to them there were never any fault codes shown at any time while the had the car and yet the valve body was changed, if fault codes weren't shown then why was the valvebody replaced ?
"no fault codes do not mean no fault. They are now further testing the car.
Out of interest what would any of the learned members of this forum suggest as the next step ?

 

[Joe Dosaj]

7G Gearbox Problems

Clk 350 Convertible

I have the clunking problem from 2nd to 1st. Also there is a slow engagement. After denying the gearbox shunted. The top mechanic at Bromley Mercedes admitted it, as he experienced it three times during a test drive with me. He said that it was a software problem. I have had every software update to current. Despite admitting to the problem. Mercedes refused to do anything about it. I have expereinced Bromley Mercedes customer service for three years. Its is the worst customer service of any main dealer I have experienced. They have damaged my car on every occasion it has been with them.

 

[Joe Dosaj]

7G Gearbox Problems

Clk 350 Convertible

I have the clunking problem from 2nd to 1st. Also there is a slow engagement. After denying the gearbox shunted. The top mechanic at Bromley Mercedes admitted it, as he experienced it three times during a test drive with me. He said that it was a software problem. I have had every software update to current. Despite admitting to the problem. Mercedes refused to do anything about it. I have experienced Bromley Mercedes customer service for three years. It is the worst customer service of any main dealer I have ever experienced. They have damaged my car on every occasion it has been with them.

 

[Mic]

Clk 350 Convertible

I have the clunking problem from 2nd to 1st. Also there is a slow engagement. After denying the gearbox shunted. The top mechanic at Bromley Mercedes admitted it, as he experienced it three times during a test drive with me. He said that it was a software problem. I have had every software update to current. Despite admitting to the problem. Mercedes refused to do anything about it. I have experienced Bromley Mercedes customer service for three years. It is the worst customer service of any main dealer I have ever experienced. They have damaged my car on every occasion it has been with them.

To be sure to be sure.

Mic

 

[television]

Clk 350 Convertible

I have the clunking problem from 2nd to 1st. Also there is a slow engagement. After denying the gearbox shunted. The top mechanic at Bromley Mercedes admitted it, as he experienced it three times during a test drive with me. He said that it was a software problem. I have had every software update to current. Despite admitting to the problem. Mercedes refused to do anything about it. I have experienced Bromley Mercedes customer service for three years. It is the worst customer service of any main dealer I have ever experienced. They have damaged my car on every occasion it has been with them.

Yes a lousy branch to be sure, so sorry to hear of your bad news

 

[hammy]

As I undrstand it the 7G software shifts it automatically into neutral - regardless of the selector position - when the car comes to a stand. This would explain the rolling backwards. Its also responsible for hesitation at junctions as the box puts itself back into drive. The new C Class is supposed o go one further and also include satrt-stop with the 7G. Agree about the foot operated parking brake. God know why Mercedes stick with this. A decent Electro-Mechanical set-up as used by BMW and Audi would be far better.

 

[RANA_1]

Ask them to look at the TIP database with you present and check for issues with 7g gear changes 1-2/ 2-3.

See attached - found this on the benzworld - it appears in the US the information has to be made public. See also ...

The 7G-Tronic had been around for at least a year before mine was produced, and has been notorious for trouble.

I can't speak to the 7G-Tronic specifically in the G, but the most recent TSB for "All Warrantable Model Years" is dated Jan 7, 2009; so it appears that the 2009's are still not 100%.

Jan 07, 2009
P-B-27.00/38e
Revision: Addition of Bullet Pertaining to 722.930 NAG2V Sport Transmission (page 2)
All Models Equipped with 722.9 NAG2 (7G-Tronic) Transmission
All Warrantable Model Years
Pre-Authorization for Transmission and Valve Body Replacement
Required for Warranty Replacement Only

Here's a couple more for "all model vehicles":

Dec 04, 2008
S-B-27.00/112
All Model Vehicles Equipped with 722.9 Transmission- 7G-Tronic (NAG2)
Hard 1-2 Shift and/or Hard Torque Converter Lockup Clutch Engagement

Nov 20, 2008
S-B-27.60/61j
Revision: Complete Procedure Revised
All Models Equipped with 7G-Tronic Transmission (NAG2)
Uncomfortable Shift Quality of 1-2, 3-2 and 2-1 Gear Shifts

 

[dieselman]

A decent Electro-Mechanical set-up as used by BMW and Audi would be far better.

If a lot less reliable. The footbrake works just fine for me in both my cars.

 

[prm]

As I undrstand it the 7G software shifts it automatically into neutral - regardless of the selector position - when the car comes to a stand. This would explain the rolling backwards. Its also responsible for hesitation at junctions as the box puts itself back into drive. The new C Class is supposed o go one further and also include satrt-stop with the 7G. Agree about the foot operated parking brake. God know why Mercedes stick with this. A decent Electro-Mechanical set-up as used by BMW and Audi would be far better.

I have read this a few times, but my 7g doesn't roll back on hills in S or C, it doesn't feel as though it goes into neutral either