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So, in the october 2025, i change my atf using titan 7134 9 liters (include inside torque converter), then on mid march 2026, the speed sensor got “cooked”, driving to the workshop in limp mode.
The speed sensor and vgs got serviced. Unfortunately they only change atf 6 liters (which means they didnt change the one inside torque converter). And 1 month after that everytime i do cold start, the gear seems stuck at 1, when the rpm hits 2.000, the car is jerking, and the gear jump to 2 (feels like driving a manual car and you let go the clutch in a hurry after shifting gear), after that no problem driving all day.
Because tesna (my friend in w212 community) often show about his coolant temp in lufy xs, i got tempted and try to monitor my own temp, using obd2 and car scanner apps. To my surprise, the matic temp is way over the coolant temp (coolant 100 degrees, atf 115 degrees).
So i rush to the workshop, changing my atf, changing my atf oil cooler and my old atf is already murky green. After i change atf, the temperature is still slowly rising, and i drive while controlling the atf degree, it doesnt come down even when i put in N or P, while engine on, rising my rpm to 1.500-2.000, it didnt come down.
next week my final plan is open up the gearbox and torque converter, because i have 2 problems
1. The jerking everytime i do cold start
2. The atf temp that always go overheat
anyone having same problems? Feel free to share your thoughts 🙏 The temp is at the max, after this it got hit to 115 degrees slowly The old liquid i changed, murky green
Try to verify the tranny oil temperature using a proper scanner, like the baby Launch specific to MB or any mid class Autel.
As fas as I recalled during my test on OBD2 data out, which the device you mentioned LUFI XS is and OBD2 device: https://lufiau.com/products/lufi-xs-obd2-gauge ..........
Such device can not show true tranny oil temp, because tranny oil temp is not part of OBD2 protocol.
Even my oldie Torque Pro ( OBD2 apps ) is the same, using its Tranny Oil temperature it is not tranny oil temp I am reading.
Try to verify the tranny oil temperature using a proper scanner, like the baby Launch specific to MB or any mid class Autel.
As fas as I recalled during my test on OBD2 data out, which the device you mentioned LUFI XS is and OBD2 device: https://lufiau.com/products/lufi-xs-obd2-gauge ..........
Such device can not show true tranny oil temp, because tranny oil temp is not part of OBD2 protocol.
Even my oldie Torque Pro ( OBD2 apps ) is the same, using its Tranny Oil temperature it is not tranny oil temp I am reading.
while Lufi XS is obd2 device it does able to do custom PIDs so it can shows ATF temp. On my old monochrome insturment cluster with AMG menu unlocked it can shows transmission temp and the number match. (Since then I have replaced the instrument cluster with color version and lost the ability to display ATF temp in the cluster AMG menu.
The number also match with numbers shown in launch scanner.
btw, regarding Mr. @yudhi262 issue, I did ask him whether his numbers is accurate or not, but he did verify the numbers in xentry it does match. Perhaps we need to meet somewhere and plug my launch scanner
but if his numbers is correct, this explains his VGS sensors failure. I am suggestign him to post here so experts here perhaps can diagnose before he is going to do full rebuilt on his W212 2013 transmission. My guess is there is something wrong with the cooling.
On cold start, when the transmission on P the temp still ok. But when on D, that's starting to get worse.
he already replaced the ATF fluid (including the one inside the torque converter) and the cooler unit (his is separate/dedicated ATF cooler unlike me inside the radiator) but the problem still persists.
or there is something wrong witht the clutches, making the temp goes wild...
How many KM is your car and did you know its tranny oil change history since day 1 ? Often many W212 or S-Class 722.9 blue tranny oil change get neglected because MB Indonesia uses 75,000KM tranny oil change or 5 years, but free service was only 2 years if car bought new. After that, first owner simply forgotten about it or 2nd owner simply forgot about it too..
Once neglected, 722.9 tranny will develop issue and being labeled not-robust.
=============
BTW did the workshop uses original tranny oil filter element from MB ?
Was the o-ring at the snorkle of the tranny oil filter still there ?
Need to rule out slow tranny oil suction and pressurizing to the system, when and if the oil filter is bad or the o-ring missing and causing air-bubbles.
.
Speed sensor going bad on VGS module seems one of the common issue when high mileage, but tranny oil being too hot on stand alone oil cooler is not common I guess.
My tranny oil is typical 80C ish. Never seen 100+ C.
=========
Fuch Titan 7143 tranny oil color......
If thin layer.....
If dripping out of torque converter
If deeper than 5mm pool, it looks very dark
Always get new Torque Converter drain plug when draining TC......... it has special sealant, not only the copper washer.
.
Perhaps tranny re-adaptation may help with the smoothness.
Also your 7 speed tranny is code A89, yes ?
See if the worshop can adapt the COLD-HOT temperature like page 8 of the attached document........
.
The mini o-ring at B3 yellow-white plastic is very important, I hope when they fixed the VGS, the o-ring is still good. There are many o-rings inside 722.9, no kidding.
I have always wondered about o-ring life span on my 722.9 too
In any hydraulic system, o-ring health is CRUCIAL.
Dang...I forgot to ask the simplest question.
Can you confirm that the oil fill of the tranny was proper during the VGS repair ?
This sound easy but often they are not done properly based on proper tranny oil temperature. It takes time do do this properly.
Lack or under-level of oil, can also produce hotter tranny oil.
1. bought the car used. many years ago. Was working without issues, all shiftting properly. changed all the fluids including the ATF + torque converter (the blue fluid)
2. few months later, failsafe mode, VGS cooked. replaced the speed sensors and all is well This time only filling up the ATF in the pan (4L)
3. after one month VGS repaired, transmission did not shift properly (not smooth). Starting to monitor ATF temp and found out its higher than normal.
4. checking other shops, and found out the shop who repair VGS did not use the correct fluid (use 4-5L of red fluid instead the blue one!!)
5. quickly drain the whole ATF, including the one in torque converter. took 8L of ATF? this time MB blue fluid, including the radiator and the transmission cooler
6. transmission issues still persists, altough ATF temp little bit lower than before
now reconsidering to REBUILT the whole transmission, maybe now the clutch is cooked due to mixture of wrong fluid (blue + red ATF) !! or maybe trying out to reset adaptation values first?
First and foremost get a good experienced auto tranny workshop familiar with 722.9
Hoping they have the special tools and experience and proper good 3rd party parts, if not genuine parts.... for when and if total overhaul is required.
========
On the other hand, if the red fluid ( wrong fluid ) was being used only a low mileage , maybe the clutch pack of the tranny will survive because the 7G-Plus and 7G
I am assuming this tranny is not even at 100,000KM yet... today.
First find why the tranny oil is too hot, it is not difficult when the oil cooler is a stand alone.
With good thermal gun ( the image type not the laser dot type ), one can measure the IN-OUT oil pipe temperature to see if the oil cooler is doing OK.
This is a separate problem with bad shifting, so it has to be solved too.
=============
At the least try to flush the tranny fluid and torque converter one more time. This is less risky and less cost too.
Genuine MB tranny oil filter and new TC drain plug and proper fill level.
1. bought the car used. many years ago. Was working without issues, all shiftting properly. changed all the fluids including the ATF + torque converter (the blue fluid)
2. few months later, failsafe mode, VGS cooked. replaced the speed sensors and all is well This time only filling up the ATF in the pan (4L)
3. after one month VGS repaired, transmission did not shift properly (not smooth). Starting to monitor ATF temp and found out its higher than normal.
4. checking other shops, and found out the shop who repair VGS did not use the correct fluid (use 4-5L of red fluid instead the blue one!!)
5. quickly drain the whole ATF, including the one in torque converter. took 8L of ATF? this time MB blue fluid, including the radiator and the transmission cooler
6. transmission issues still persists, altough ATF temp little bit lower than before
now reconsidering to REBUILT the whole transmission, maybe now the clutch is cooked due to mixture of wrong fluid (blue + red ATF) !! or maybe trying out to reset adaptation values first?
How many KM is your car and did you know its tranny oil change history since day 1 ? Often many W212 or S-Class 722.9 blue tranny oil change get neglected because MB Indonesia uses 75,000KM tranny oil change or 5 years, but free service was only 2 years if car bought new. After that, first owner simply forgotten about it or 2nd owner simply forgot about it too..
Once neglected, 722.9 tranny will develop issue and being labeled not-robust.
=============
BTW did the workshop uses original tranny oil filter element from MB ?
Was the o-ring at the snorkle of the tranny oil filter still there ?
Need to rule out slow tranny oil suction and pressurizing to the system, when and if the oil filter is bad or the o-ring missing and causing air-bubbles.
.
Speed sensor going bad on VGS module seems one of the common issue when high mileage, but tranny oil being too hot on stand alone oil cooler is not common I guess.
My tranny oil is typical 80C ish. Never seen 100+ C.
=========
Fuch Titan 7143 tranny oil color......
If thin layer.....
If dripping out of torque converter
If deeper than 5mm pool, it looks very dark
Always get new Torque Converter drain plug when draining TC......... it has special sealant, not only the copper washer.
.
Perhaps tranny re-adaptation may help with the smoothness.
Also your 7 speed tranny is code A89, yes ?
.
I bought that car on 2023, July the km was around 33.000, full service record from cakrawala
I directly flushed it after i bought it
As far as i know the workshop use original tranny elements from MB, but i dont pay attention to the O ring
My liquid is like your photo, turn green, only murkier/ darker
Now my km is around 78.000 (i use it daily)
The new torque converter drain, i will ask the mechanic tomorrow
The blue ATF you need is thinner than the red ATF that was in there.
So you had a bit more pressure than intended before adaptations really got confused.
You have already flushed the whole system
I would try to redo your adaptations.
yes, the most f*cked up day in my life when the mechanics serviced my vgs just playing ignorant while saying “red or blue? Its just the same, red is the best anyway”
i just yelling in silence, “IF RED IS THE BEST? WHY THE HECK MB CREATES BLUE ANYWAY??!!”
I saw the 2 videos from Tesna.... the 722.9 main body/casing is magnesium.
Its less corrossion resistance than aluminum, but I did not expect for the magnesium its to be that "flaky".
Lots of mettalic debris is also from the clutch material.
I hope the repair goes well yah. Clean them all.
=========
So the MOD or system, kept this thread "gone" for 3 days.
yes, the most f*cked up day in my life when the mechanics serviced my vgs just playing ignorant while saying “red or blue? Its just the same, red is the best anyway”
i just yelling in silence, “IF RED IS THE BEST? WHY THE HECK MB CREATES BLUE ANYWAY??!!”
The automotive engineers keep evolving their designs non-stop:
the coolant chemistries
the ATF fluids
the engine lubricants
the brakes DOT fluids
the differential gear oil
the windshield washer
Sometimes upgrades, sometimes downgrades...
in the end, modern fluids have a more narrow operating range, shorter lifespan such that it is always punishing to extend service intervals.
The fluids go from bare bone specs to out of grades with HEAT as enemy.
Last edited by CaliBenzDriver; May 20, 2026 at 10:18 AM.
I saw the 2 videos from Tesna.... the 722.9 main body/casing is magnesium.
Its less corrossion resistance than aluminum, but I did not expect for the magnesium its to be that "flaky".
Lots of mettalic debris is also from the clutch material.
I hope the repair goes well yah. Clean them all.
=========
So the MOD or system, kept this thread "gone" for 3 days.
the video is nasty... I was suprised it can do that@yudhi262 please post the video here so others can see. I looked around on youtube I think no one has experience this before :O (altough the shop said it has found this case serveral times :O)
According to Gemini:
What Is That Coating?
The inside of a Mercedes-Benz Magnesium Alloy transmission case is often coated from the factory with a specialized, oil-resistant anti-corrosion sealant or paint (often an industrial equivalent to something called Glyptal).
Manufacturers use it inside raw castings for two main reasons:
Sealing the Porosity: To seal microscopic pores in the cast aluminum so high-pressure ATF doesn't sweat or seep through the metal walls over time.
Trapping Casting Sand: To lock down any microscopic leftover sand from the factory foundry molding process so it doesn't break loose and clog the hyper-sensitive VGS valves.
Why Did It Disintegrate?
Under normal conditions, this factory coating is engineered to last the lifetime of the vehicle. It is highly chemical and heat-resistant—until it gets baked.
The $115^\circ\text{C}$ Oven effect: Your friend’s transmission was running at $115^\circ\text{C}$ (and likely higher before he started monitoring it) for extended windows, such as that grueling 6-hour non-stop drive.
The "Red Oil" Chemical Attack: Compounding that severe heat was the chemical mismatch of running the wrong, thicker Red ATF. The incorrect fluid chemistry, combined with localized boiling temperatures at the slipping clutch plates, physically broke down the polymer bonds of the factory paint.
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.
