SL350 R230 - Gear changing problems

[poleman]

Hello everybody

I am the owner of a R230 SL350 , 2005 model (3750 ccm, 245 bhp).
The last few months, randomly the gearbox refused to change gears up or down, and was stuck to the gear that was engaged at the time. I found out that (like some other issues) when the car was switched off and back on again, the problem dissappeared... until last week. The problem appeared again, also with a noticeable kick while driving (the kind that was felt when the first automatic cars were changing gears back in the days), but the difference is that no matter how many times i switched off and back on, the car would only go to 1st gear or reverse (always with the noticeable kick).
I visited the workshop, they opened the gearbox to check for damage or evidence of mechanical problem, but they said everything was fine. They have reset the error codes and tested the car for 15 miles, and said tht the problem disappeared. When i drove the car again, it started the symptoms within the first 5 miles of city driving and soon it was stuck again to 1st gear.
They are now suggesting that it is the electro-hydraulic valve (part nr. A 211 270 00 06 80 ). As it is clear that it is not a mechanical fault but an electronic (or hydraulic) one, I am wondering if there is a microchip or a printed circuit board that needs changing, and not the £1200 part mentioned above. The garage told me that the only controller involved in this is this valve part (no separate circuits etc exist as parts).
Basically I am looking for your opinion and if there is a way to avoid paying this hefty bill.
I apologize for the lengthy post - any help mostly welcome. Thank you

 

[Codger49]

Probably best to post your VIN, then someone can check which variety of gearbox is fitted to your car.

If you have the 7 speed 722.9 box, then your workshop may be correct. This has an electroplate which often fails (don't ask me how I know).

The key is whether your box is an early one (VGS), in which case the valvebody and electroplate have to be replaced as a unit; or whether it is a VGS 2 box in which the electroplate alone can be replaced (around £600-700).

PS Your symptoms do match a 722.9 electroplate failure.

 

[poleman]

Probably best to post your VIN, then someone can check which variety of gearbox is fitted to your car.

If you have the 7 speed 722.9 box, then your workshop may be correct. This has an electroplate which often fails (don't ask me how I know).

The key is whether your box is an early one (VGS), in which case the valvebody and electroplate have to be replaced as a unit; or whether it is a VGS 2 box in which the electroplate alone can be replaced (around £600-700).

PS Your symptoms do match a 722.9 electroplate failure.

Thank you very much for your reply Codger.
My gearbox is a 5-speed, car model year 2005. I will check and advise on the serial number. I was told that there is no separate hydraulic and electronic parts, but only one part that combines both. To be honest this comes as a surprise, as for this highly electronic car (if i am not mistaken it has 3 computers) it makes more sense to have separate electronic circuitry..
So, if i understand crrectly, you concur that it is one part..

 

[Codger49]

The 5 speed 722.6 does have a conductor plate which is attached to the valve body.

If you do a Google search on "722.6 conductor plate" you will see many owners have replaced the plate on its own. Whether you need to replace the plate and/or the valve body as well will depend on the actual fault your gearbox is experiencing.

I guess it depends how much you trust your garage, many members on here would recommend using a reputable independent (e.g. PCS in Horndean, Wayne Gates in Harrow etc etc), who would use MB Star diagnosis to pinpoint the issues.

If you have been given fault codes, it would be worth posting them here as one of the more technical members could then comment on likely remedies.

Basically, I think a second opinion is advisable - its not a cheap repair and the info from your garage could be more clearly expressed.

 

[flowrider]

My experience of MB workshops is that they replace parts until they find the cure then charge you for all the new parts whether needed or not, when you ask for the old part back it has mysteriously dissappeared. My ML has a very discrete dashcam and i see what goes on when the car was last serviced, bonnet up, 5 mins fiddling under the bonnet, oil change for 15mins or so another 10 mins fiddling, bonnet down car done, that'll be £800 sir!

 

[poleman]

The 5 speed 722.6 does have a conductor plate which is attached to the valve body.

If you do a Google search on "722.6 conductor plate" you will see many owners have replaced the plate on its own. Whether you need to replace the plate and/or the valve body as well will depend on the actual fault your gearbox is experiencing.

I guess it depends how much you trust your garage, many members on here would recommend using a reputable independent (e.g. PCS in Horndean, Wayne Gates in Harrow etc etc), who would use MB Star diagnosis to pinpoint the issues.

If you have been given fault codes, it would be worth posting them here as one of the more technical members could then comment on likely remedies.

Basically, I think a second opinion is advisable - its not a cheap repair and the info from your garage could be more clearly expressed.

Thanks again. This is exactly what i am after... I have already paid 2 hours something for the MB shop checking error codes, then further checking the "transmission" (they said they even checked for filings to see if there was damage in the gearbox) and putting back together.
A 2-hour browsing the net found me that the most common problem of the 722.6xx transmission, was oil migration to the plug of the conductor plate, so the easiest remedy is -if oil is evident- to clean and put back together. It also found me what i suspected i.e. that the electronic part (conductor plate) is separate than the hydraulic part, and costs 1/10 of the price !
As i suspected in the 1st place, i am heading towards being taken to the cleaners.... Unless someone has a different opinion to share, i am gonna have a word with this MB shop Monday morning!
here's some interesting videos
https://www.youtube.com/watch?v=bdt4g5jqo4E
https://www.youtube.com/watch?v=k3qrSDfK7SA
https://www.youtube.com/watch?v=QvwxeCy8xRQ
... ain't todays technology a marvelous thing !

 

[Shuki]

Hello everybody

I am the owner of a R230 SL350 , 2005 model (3750 ccm, 245 bhp).
The last few months, randomly the gearbox refused to change gears up or down, and was stuck to the gear that was engaged at the time. I found out that (like some other issues) when the car was switched off and back on again, the problem dissappeared... until last week. The problem appeared again, also with a noticeable kick while driving (the kind that was felt when the first automatic cars were changing gears back in the days), but the difference is that no matter how many times i switched off and back on, the car would only go to 1st gear or reverse (always with the noticeable kick).
I visited the workshop, they opened the gearbox to check for damage or evidence of mechanical problem, but they said everything was fine. They have reset the error codes and tested the car for 15 miles, and said tht the problem disappeared. When i drove the car again, it started the symptoms within the first 5 miles of city driving and soon it was stuck again to 1st gear.
They are now suggesting that it is the electro-hydraulic valve (part nr. A 211 270 00 06 80 ). As it is clear that it is not a mechanical fault but an electronic (or hydraulic) one, I am wondering if there is a microchip or a printed circuit board that needs changing, and not the £1200 part mentioned above. The garage told me that the only controller involved in this is this valve part (no separate circuits etc exist as parts).
Basically I am looking for your opinion and if there is a way to avoid paying this hefty bill.
I apologize for the lengthy post - any help mostly welcome. Thank you

Hi, I am located in Israel and driving the same car

R230 SL350 , 2006 model (3750 ccm). I have exactly the same phenomena. What was the problem of your car? How did you solve it?

Thanks

 

[Shuki]

R230 SL350 , 2006 model (3750 ccm). I have exactly the same phenomena. What was the problem of your car? How did you solve it?

 

[ernie]

R230 SL350 , 2006 model (3750 ccm). I have exactly the same phenomena. What was the problem of your car? How did you solve it?

Unlikely to get an answer - that guy was last seen here in October 2016!

Ernie