Clk 722.6 gearbox issues

[Ginettaman]

My 2005 320clk box is occasionally showing issues that reset with the ignition off and on again. I have had times where it doesn't go into top gear and today swimbo said she had no reverse until a second go? It's done nearly 90k miles so my first thought was a gearbox service but on doing some web reading I see people also blaming the plastic conductor plate in the box? I'm an experienced self taught mechanic but before attempting work wanted to ask a few questions. I'm new to the Clk but have already changed the crank sensor front calipers and top gaskets since buying.
Firstly where is the obd socket and will an ordinary code reader find a code for the box?
Who supplies a reliable replacement conductor plate as on eBay they all look the same but prices range from £25 - £160? I could end up paying say £80 for a £25 part as they look the same but guess they are not!
What version of the box will my car have?
Are all the conductor plates the same fit or are there different versions?
Do I need 7l of oil?
Which atf oils are ok to use?
Do I need to buy a gearbox dipstick? (I don't have one for the engine either which is annoying ?)
Are the boxes filled from the dipstick hole in the engine bay behind the V?
How do I drain the torque converter?
Does the whole process need a main dealer gearbox reprogram or not? 5 speed not 7?
If not does the box need a reset after the replacement and how is that done?
I see the electric sockets are blamed along with oil creep but what actually breaks on the conductor plates?
Could it just be a bad socket connection?
Who has done the job recently?
Thanks I'm near York if anyone local is experienced?

 

[Dodipops]

Think euro car parts do the conductor plate. It is a really common fail and if changing I would change the pilot bushing (electrical connector sealing plate) as well. If this shows sign of leaking oil then it’s worth a look at the transmission control module for sign of capillary oil in there.
You don’t need 7 litres more like 4 and it’s red atf mb236.14 spec.
You will need a dipstick and it’s filled from dipstick tube and the level checked running.
As far as I’m aware the conductor plates are all the same and you don’t need to programme or relearn any settings just erase codes, not sure if a cheap one scanner will do gearbox.
Mind you’ll need a new filter, gasket and I’d recommend new bolts for the sump pan.

 

[alabbasi]

ASR or ABS light come on when it acts out?

 

[Dodipops]

No not usually anyway. If these systems have warning lamps on then I would rectify these faults first.

 

[Ginettaman]

No warning lamps as yet but will check Pilot plug for leaks as some just replace the O rings on them I read.

 

[Petrol Pete]

This box is fitted in tens of thousands of cars and trucks worldwide. The service on it is all over the internet , service kits are sold by hundreds of suppliers (including MB) as are conductor plates etc. The work is well within the scope of any decent DIY mechanic with the correct kit.

A full fluid change including TC and cooling will need around 8.5 litres. Changing the TCU plug (complete) at the same time is a 'no brainer' as even a genuine MB one is cheap, as are new sump bolts (which can snap) you will need a torque wrench that goes low 5..or 8Nm from memory.

Or just get the job done by an MB indy or any gearbox specialist, £250/£300.

 

[andy27168]

Hi,
Just try to top up the fluid, as the symptoms you are describing suggest to me low fluid level.
Do ensure you use the correct fluid.

 

[alabbasi]

No warning lamps as yet but will check Pilot plug for leaks as some just replace the O rings on them I read.

If it's going into limp mode, it would usually throw a code that can be read by a 1/2 decent scanner. Try locating the TCM to see if the connector is wet. If the gearbox starts leaking at the electrical plug, the fluid will run up the wires and make its way to the TCM.

Replace the plug, but clean the TCM also.