CLS220 Shooting Break 2015 ATS Problem 722.9 7 Speed

[Pmac83]

Evening All,

I recently had my CLS services (60k miles) 5-year service which included a transmission filter and oil change as recommended (75k miles or every 5 years).

Before the change, the vehicle gearbox was silky smooth with no issues. However, since the change the ATS has been very clunky on changes and on three occasions in low gear/speed has randomly shifted down which has thrown me forward in the car.

The following parts were used:

a. Auto Trans Filter kit Mercedes 722.9 7 speed with gasket and screws.
b. MPM ATF Automatic Transmission Fluid MB7S MB 236.15 Total 8L.

Does anyone know what could have gone wrong?

 

[malcolm E53 AMG]

Welcome!

The 7spd transmission can be temperamental unless perfectly set-up, first points to check are fluid level and whether there is a software update. Who did the gearbox service MB or Independent?

 

[Pmac83]

Welcome!

The 7spd transmission can be temperamental unless perfectly set-up, first points to check are fluid level and whether there is a software update. Who did the gearbox service MB or Independent?

I got it done by an independent, not an MB specialist either. Starting to regret it now!

I will take it back to the garage and see what they say.

 

[malcolm E53 AMG]

This might help:

https://blog.fcpeuro.com/mercedes-7-speed-transmission-service-walkthrough-722.9-transmissions

 

[Uncle Benz]

This might help:

https://blog.fcpeuro.com/mercedes-7-speed-transmission-service-walkthrough-722.9-transmissions

couple of things I don’t like there - they don’t even mention draining the torque converter, and measuring the temperature with the back of your hand is not accurate enough. The fill level is critical to correct operating on these gearboxes.
Many independents used to reset the adaptations when conducting a gearbox service on the older 5G 722.6 transmission. In my experience it’s not a good idea to do that on the 722.9 7G. It leads to thumpy changes. It should readapt, but it can take up to 100 miles to get back to where it was. It might be worth asking your independent if they did this

 

[Pmac83]

couple of things I don’t like there - they don’t even mention draining the torque converter, and measuring the temperature with the back of your hand is not accurate enough. The fill level is critical to correct operating on these gearboxes.
Many independents used to reset the adaptations when conducting a gearbox service on the older 5G 722.6 transmission. In my experience it’s not a good idea to do that on the 722.9 7G. It leads to thumpy changes. It should readapt, but it can take up to 100 miles to get back to where it was. It might be worth asking your independent if they did this

Called garage today and said they will have it back in to check it out. I asked about resetting adaotations and didn't seem to get what I was meaning.

There hasn't been anymore violent change downs today, but still clunky 1 to 4.

 

[Pmac83]

Update, the garage had the vehicle back in and confirmed the levels and everything are correct. There are no outstanding software issues and it has been driven over 300 miles since the change. Unfortunately, the problem still remains.

The issue only happens at slow speed and is sporadic. It seems to go to change gear but fails example: D3 it will start to slow the vehicle will lurch the vehicle will show D before finding the correct gear.

Any new thoughts?

 

[alexanderfoti]

I'd ask how they are checking the level?

Alternatively, there may be a fault with the filter they have fitted, but I can't imagine so.

Possibly get a second opinion from a second garage.

 

[Pmac83]

I'd ask how they are checking the level?

Alternatively, there may be a fault with the filter they have fitted, but I can't imagine so.

Possibly get a second opinion from a second garage.

They provided me with print off of the manufacturer filling process and have said they followed the process exactly. They said they are monitoring the temperature through the computer. Would they be able to see the fill level through the computer? or is it simply following the filling process?

Thanks for your advice so far.

 

[alexanderfoti]

They provided me with print off of the manufacturer filling process and have said they followed the process exactly. They said they are monitoring the temperature through the computer. Would they be able to see the fill level through the computer? or is it simply following the filling process?

Thanks for your advice so far.

No but it does sound like they have done the job exactly to the book. I'd check for something else maybe a broken drain tower allowing too much oil to be drained off during the level check process.

The level cannot be checked on the computer unfortunately

 

[Steve@Avantgarde]

Sounds like an incorrect oil level to me...

 

[Wighty]

Incorrectly coloured (size) plastic drain tower fitted ?

 

[Steve@Avantgarde]

Are the towers different sizes? I though one was white and one was green to differentiate oil type..I've never paid any attention to their lengths...

 

[alexanderfoti]

Are the towers different sizes? I though one was white and one was green to differentiate oil type..I've never paid any attention to their lengths...

They are, its dependent on pan design.

 

[Wighty]

They are, its dependent on pan design.

That was a close one ,I was nearly wrong

 

[Pmac83]

Incorrectly coloured (size) plastic drain tower fitted ?

Would this have been changed in an oil and filter change or is it part of the oil tray? This is the first time it would have been removed since the vehicle was manufactured, as it was the first time the oil and filter were due t be change.

 

[Pmac83]

Further update. On driving the vehicle back to the garage, the laboured changes were constant and the vehicle was struggling to drive and the EML turned on. I am still waiting to find out what error codes are present from the ATS ECU and vehicle ECU.

Having read some more sources on line a common theme which has come up is a TCM conductor plate failure. Has anyone come across this before?

Would driving a vehicle with low transmission fluid cause a failure with TCM conductor plate or one of its sensors?

 

[Wighty]

Would this have been changed in an oil and filter change or is it part of the oil tray? This is the first time it would have been removed since the vehicle was manufactured, as it was the first time the oil and filter were due t be change.

It is possible to re use them , but I would guess most change them for new because they are cheap . They differ in colour and length depending on which gearbox . If the wrong height one is used , that will make the level of oil in the gearbox wrong

 

[malcolm E53 AMG]

Very often the plastic filler/level tube is displaced/punctured in order to drain the pan then when the pan is removed replaced with a new one

 

[alexanderfoti]

Yes they break quite often, or crack. I always replace them.