@.Griff. Now the bad news.

If they replaced the oil in the Left and Right clutch packs (as opposed to the centre hypoid diff gear section) - they have used the wrong oil …..

They are supposed to use 235.64.

Part No: A000 989 4406

See section 9 of this table

Mercedes-Benz Operating Fluids

Publication platform for approved operating fluids from Mercedes-Benz

operatingfluids.mercedes-benz.com

My first question to them would be -

Which part of the diff did you replace the oil in?
The centre section, or the Left and Right Clutch sections?

Because you have indicated you’ve replaced the fill and drain plugs on both sides (Qty 4) so it would appear that you’ve replaced the oil in the L&R clutch sections …… in which case you’ve used the incorrect oil?

 

But if they have replaced the centre section oil, then it’s the correct oil. But why have they used 4 screw plugs?

The invoice lists part no A000989360811 which is 235.63 oil, which is correct for the centre section. Not the L&R clutch packs.



For your own sanity, I suggest you read this thread carefully….

https://www.aclassclub.co.uk/threads/a45s-rear-diff-oil-and-oil-changes.23824/

 

I appreciate the above but I've exerted enough time and effort on this so far and need to focus on other matters.

While specifics are important, of course, the noise has gone away and the vehicle has two more years remaining warranty so in the event that have used the wrong oil then it's covered as a far as I am concerned and the car will likely be moved on before the warranty has expired anyway.

The purpose of my chasing for the final invoice was to aid others, in future, who may have the same symptoms and who wanted something tangible to use as 'persuasion" to get their respective dealership to act.

EDIT - See https://www.aclassclub.co.uk/posts/220584/

 

If an MB garage can do this it probably means many of us are also getting the wrong oil. Which is something @Theo was very concerned about previously.

 

The invoice says they used 0.5L so it appears they did the center section, else you only have 0.25L per side if they did the twin packs. I just can't believe they would be this dumb. I find it easier to believe they drained the twin packs just to check on the oil and put it back in and a full plug replacement went with it.


And it was even worse in my case because instead of the 235.64, they sold me the oil that is meant for the standard, single clutch 4MATIC (i.e. A250), which is the 235.15 and thanks to the forum here I was able to print out the official MB operating fluids sheet and rub it in their face. They still looked at me like I was some kind of a strange being, just to be clear. How is it when you stumble on something that radically changes everything you knew? Hard to accept, but also impossible to deny? And it was only then, that the correct order for 1L of 235.64 in that Shell bottle was placed and the 235.63 a little after (when it became available) to do the center section which they said isn't meant to be changed, but the chief mechanic agreed with me that an oil change will always be for the better.

Mercedes-Benz Operating Fluids (last page)
Mercedes-Benz Operating Fluids (second page)

 

So I found myself with 20 minutes spare - I have emailed MB UK (as they sent me a courtesy follow-up email last night).

I won't paste the contents in here as it's lengthy, and technical but I can summarise the email as follows -

Can you please confirm exactly what work was carried out on my vehicle -

1 - Was it the centre section of the diff or the left and right clutch packs?

2 - If the response is the centre section can you then clarify why four screwplugs were used?

3 - If four screw plugs were used because the oil was changed in the left and right clutch packs why was the wrong specification of oil used?

To aid the above I included a copy of the warranty invoice and a copy of MB document "231.1 Specified gear oils (cars, cross-country vehicles, vans) - overview" drawing their attention to the pertinent entries on it.

 

Following your correspondence, I have approached Mercedes-Benz of Shrewsbury in relation to your enquiry related to the oil changes of your vehicle.

The technical team has advised us that they did not change the oil in centre gear set, but only in the left and right clutches, and the oil that was used was "Shell TF0870B", and it was due to a mistakes that the standard oil was booked originally on the warranty invoice.

So the definite response is that the Shell oil was the one used to the left and right clutch pack units.

We hope that the above information addresses all your concerns and resolves the matter for you.

Checking 235.64 does show Shell TF 0870 B as the correct specified oil for the rear clutch packs.

I guess this is a lesson for MB to provide the customer with accurate documentation to start with rather than "We've fixed it, now please be on your merry way".

 

I guess this is a lesson for MB to provide the customer with accurate documentation to start with rather than "We've fixed it, now please be on your merry way".

There’s the question of the incorrect quantity on the invoice, but let’s be charitable and attribute this to the same booking/admin/invoicing mistake

Lookers Shrewsbury need to learn from this and up their customer service game.

 

Have there been any reports of the noise returning after the "fix"?

It's been 4 months since the oil was changed in the rear diff clutch packs and I'm sure I can hear the noise returning when I pull away. Nowhere near as obvious as before but I'm sure I can hear it.

I've only done about 1500 miles in that time and none of it has been especially spirited.

 

Take it back to MB. The oil change makes a difference.

 

The oil seems to be critical to the operation of the diff hence any subsequent noises I would take it back.

 

Yes I agree it should be taken back.

However it appears that you didn’t fully properly read the previous post and completely missed that the poster only had a rear diff oil change 1500 miles ago, of which we covered in nauseating detail in this very thread, because of the lack of detail on the invoice!

This is the second time you’ve misread this poor posters posts, he might be getting a complex that you’ve singled him out (on the first occasion, accusing him of editing his post!!!)

 

@.Griff.

I would get them to check for a worn flex plate, just in case.

(even if your VIN might be outside the scope of the recall)

See

https://www.aclassclub.co.uk/threads/a45s-flex-plate-recall.25792/

 

Have a look at post 34 onwards in that thread mate 😊