Guys and gals. This is not intended to cause alarm but to respectfully suggest that you service your 722.9 transmission every 39K miles or 60K Km's as in ROW. We are seeing an increased number of TC et al failures as mileage increases & feel it prudent to inform you while we try to fully understand the failure mode. We should also state that forums such as these concentrate problems as many only post when they have a problem.

https://mbworld.org/forums/c-class-w...need-help.html

Does this include Manual Transmission service at that interval. Thanks.

No!

Thanks for the advice Glyn. What is the OEM fluid manufacturer and spec? What is a comparable aftermarket? Is there a drain for the torque converter as well and must this also be done. Thanks again.

cheers! Mike

Thanks LSA!

Go here to my W209 version for a little added info to John's great thread.

https://mbworld.org/forums/clk-class...ce-thread.html

What is the transmission number on my 2012 GLK350 4matic? If I have a 722.9, would 30k miles be OK? That is an easy number to remember.

Wayne

You have the latest 722.9 tranny. 30K mile services would be great.

Just had both my B and C transmission serviced at below 60,000km. What are your thoughts on brake fluid flush, I haven't done that and at this point don't really believe in it. Is it a must?

Brake fluid should be flushed every 2 to 3 years. Brake fluid is hygroscopic i.e. it absorbs water. Aside from brake fluid boiling at the wheel if water content gets too high & resulting in brake failure, the cost of a new ABS block these days if it gets contaminated & damaged by corrosion by-products is also high & remember the ABS pump semi circulates the fluid.

Flush your brake fluid. It's a very minor job for the potential savings & safety issues.

Thank you for the links. Much appreciated. It appears all of them on the list are not fully synthetic lubricants including the one that touts itself as factory fill. Has anyone found a higher quality fully synthetic fluid that is within the same specs as those on the list?

Thanks

cheers! Mike

These are the latest & only approved fluids. Presume you are only talking ATFs & not brake fluid? There is only one approved additive system & these are the ONLY fluids that should be used.

Here:

Ryder fleet products have by far the best deal on this product by Shell at under US$ 6 per quart. Most dealers are charging over $20/quart. The Shell product is fully approved. Many use Fuchs Titan 4134 as well.

See description. It is Shell product in a Shell container - Pennzoil is owned by Shell. Many have confirmed correct product in Shell packaging on receipt.

http://www.ryderfleetproducts.com/ry...oductDetail.do

I can definitely appreciate those on the approved list but i'm also wondering about more longer term than satisfying warranty requirements. If we in the US had taken MB word for it we'd be thinking this non synthetic fluid is a "lifetime" fill. So knowing MB (or anyone) is not always perfect with their recommendations, i'm wondering if anyone has found a higher quality fully synthetic with greater shear stability, similar cold and hot viscosity, etc that would work better than the approved ATF that uses group III base stocks. Fluids like Pentosin ATF or Liqui Moly ATF 1600? Would they be better?

http://www.pentosin.net/pressrelease...in_ATF1_V3.pdf

http://www.liqui-moly.de/liquimoly/m...%201600_EN.pdf

http://www.redlineoil.com/product.aspx?product=30704


Just curious. If there is evidence that fluids like this will not be better that's ok but I had to ask for curiosity sake if there is a better option out there that the oil experts know of.

Thanks. Mike

No they won't. It's a good question which I can answer very simply. Full synthetic or very high Group number base oils, GpIII & above have their downfalls. Additive miscibility steadily becomes more & more of an issue. i.e. the additive will not dissolve or disperse in the base oil.

So to achieve the desired performance we use the synthetic base fluid for the high VI, oxidation stability etc. properties it brings to the formulation while using a small proportion of petroleum base stock as a co-solvent to get the additives into the blend & stable.

100% synthetic is not always better - in fact far from it.

Don't worry. Benz & the oil industry have really done their homework on this product through it's many generations from 236.1 to 236.14.

Thank you Glyn for that concise and helpful response. I'm set at ease a bit more when choosing a fluid.

cheers! Mike

Thanks Glyn. I have made a note on the schedule that was supplied with our 2012 GLK350 4matic.

Cheers!

Wayne

I think i'm going to drop mine down to a 30K mile service. The cost of a fluid change is nothing compared to replacing transmission parts. Plus, that number is easier to remember.

In fact - Johnand - who I consider the board's guru on this transmission is advising a 30K change to all W203 members who have the early generation & more troublesome versions of this transmission.

Good to know. Thanks Glyn!

There you go.

Wayne

I wish we had this sensible response from all. On the W209 forum we have an Indy recommending the use of non-approved Valvoline Maxlife which has the wrong frictional properties just to start with. We support Indy's on this forum & it makes me mad when they somehow think they know more than the designers of the transmission working in conjunction with the oil industry to look after their design & their customers.

I just called my dealer (where I purchased the car) as well as the MB dealer most local to my place of business. My dealer quoted $459 for the trans flush/service while the dealer close by work quoted $365...

Any clue why the service prices vary so much for the same job (fyi - I also looked on line for specials and there is a dealer by the name of Hoffman MB in Illinois, if I remember correctly, quoting $299 for the same service)

Also - I questioned both service managers regarding the torque converter being drained and received the same reply from both "We no longer pull the trans to complete the service, therefore the torque converter is not included" - Glyn, is this accurate?

I am at 42K miles, last service was at 34k and I was told at that point to wait until service indicator for the next due service was on, and complete the trans at that time...

I can't believe these @ss---- dealers. You don't have to pull the transmission to change the converter. There is a rubber plug in the bellhousing. You remove it, rotate the engine until the TC plug lines up. You undo the plug & drain the converter.

The converter MUST be drained. It holds 4 litres of oil - nearly half the charge. Just insist they do it. Take the latest WIS method from Johnands service thread in the stickies & tell them to follow it EXACTLY.

Don't know why prices vary. The parts & fluid cost is nearly $200.

Follow the link in this thread:

https://mbworld.org/forums/c-class-w...ce-thread.html

Open and print this PDF:
2)Automatic Transmission Oil and Filter Change - This is the latest up to date MB WIS document on how to service the transmission.
You may also want to print the torque converter draining instructions.

EDIT: And this...

https://mbworld.org/forums/clk-class...ce-thread.html

Take this information to the dealership. Show them that you know what M-B requires for a fluid & filter change. Watch them crawfish and squirm.

Wayne