Mercedes 722 9 transmission flush

Flushed my wife's SLK 350 R172 transmission fluid 722.9 is the model of the tranny
Found out that I can't drain the torque converter!!

[@drewprof]

That's on my list of work to do. I just got a lift but I have yet to install it.

[@maintainersgarage]

Lift makes it easier!

[@davidsalaki453]

I am trying to perform a trans fluid flush on my wife's '19 SLC 43. Do you know if there is a transmission cooler return line that you can remove to flush out dirty ATF while keep on adding new fluid until the return line fluid becomes clean (basically using internal trans pump to push the fluid out). I performed this flush method on many other makes and models (Lexus, BMW, Infiniti, etc). This is going to be my first attempt on a Mercedes 722.9 :)

[@maintainersgarage]

I don't know about the transmission cooler or return line

[@ukaszjurys2475]

would you use transmission oil cleaner prior to change of oil or better not to "clean" it that way ?

[@maintainersgarage]

This is putting fresh fluid in, so I think this would be best

[@fredsalfa]

Does the torque converter oil need to be changed? And will my dealer or specialist have the special tool? My car only has 11,000 miles or 17,000 km on the clock but it’s a 2012 model or it’s 12 years old and the transmission oil hasn’t been changed ever from new. I feel like the gears won’t change up normally in sport mode although economy mode gear changes are fine. Everyone says I need to change the transmission fluid first thing.

[@maintainersgarage]

Does the TQ converter fluid need to be changed, IMO, yes. You go through the motions to get as much old fluid out as possible. And i agree, change fluid 1st before trying to diagnose problems. And YES dealership should have all tools required

[@fredsalfa]

@@maintainersgarage Ok thanks. Specialists want to charge me $800 Aussie Dollars (Similar to US) and dealer $1,500 or something

[@maintainersgarage]

@@fredsalfa if specialist is well rated, go with them!

[@Armcock]

@@maintainersgarage for anyone else looking to get it done, they pump it out getting all your fluid out with a vacuum pump and replacing it with the exact amount taken out, very good service, but can be expensive

[@maintainersgarage]

@@Armcock indeed !

[@danh8364]

Does the car have a dipstick?

[@maintainersgarage]

Oil dipstick yes, tranny dipstick NO

[@juicebox22a]

Nice video. The Four dimples on the pan indicate a initial fill of red colored ATF and should have a black or white fill tube. No dimples on the pan indicate an initial fill of Blue ATF (A89 option code) and should have a green fill tube. To access the torque converter drain you need to rotate the crankshaft pulley which will move the drain plug into a more accessible angle.

[@maintainersgarage]

I did rotate the crank bolt this spinning the tq converter, the drain screw is not accessible. But, interesting info on the pan and fluid

[@TheTMog]

Had the same thing on my wife's '13 GLK. TC drain plug visible but completely inaccessible. Also cut off hex key to try to access, but no good.

[@maintainersgarage]

@TheTMog glad I am not the only one! Very frustrating!!