raverx3m

2011 c300 4matic with 195k
car was raped mechanically by a clueless mechanic and the owner
they used red fluid in the updated transmission 722.9

the rpm was fluctuating and it was barely holding gears
replaced fluid with proper one (drained tq and transmission)
and it drives alot better now no rpm wobble and shifts smooth most of the time
when warm it shifts reasonably well for that mileage

when cold the first gear(in sport mode) and second gear( in economy mode) there is a delay in gear engagement.
especially when i take off uphill
i can feel the clutch disengage and almost a second later itengages with next gear.
doesnt happen in any other gear.
also is dependent on the driving mode S or E
so its not the clutches
because if it was both first and second gear clutches it would do it in both gears in sport mode

im suspecting its the TQ going out?
or is it something else i should look into?
there are no transmission or engine codes. just few codes for some stupid fuse box g31 circuit and bunch of other electrical interior stuff...



also what would be the signs of glycol contamination ?

Odd Piggy

If the shift delay goes away after the transmission gets up to operating temperature, that sounds like a viscosity problem with the fluid. Did you drain the transmission to get the red fluid out, or did you do a flush? Maybe some of the old fluid is contaminating the new.

raverx3m

i drained pan and torque converter not an actual flush
i have to do one more drain to get more out
the shift delay wasnt there initially.
it showed up over time as the rest of it became better the shift delay got worse

if its a viscocity issue why does it only show up in first and second gear uphill and no other gear?

its actually starting to show up when warmed up also

Odd Piggy

My fluid viscosity observation was based on it going away/getting better when the fluid warmed and viscosity dropped. The old red fluid was higher viscosity and contamination might make it too thick when cold.

The fact that it’s beginning to happen when warmed up probably makes this an unlikely cause.

Torque converter failing on an uphill grade would be under load where those failures are usually most noticeable. But my experience is that they’re also seen in the higher gears because the load on the converter is higher. The one that I had fail was noticed in high gears first before it happened in all gears.

I did see one post on another site where red fluid had been added accidentally. Blue fluid was put in at some later time, but the red fluid caused glazing of the lock up clutch plates, resulting in a similar problem to what you report that could not be fixed by changing fluids.

Now for some FYI stuff [if you have a 722.9 power flow chart, just ignore this]:
To shift from neutral to 1st, brake B2 is applied by solenoid Y3/8y6
To shift from 1st to 2nd, B3 is released by Y3/8y7, and B1 is applied by Y3/8y5
Any other components are common to more than 1st & 2nd gears, so should not be an issue.

Before you invest time and money in a new torque converter, you may want to monitor the transmission shift patterns in real time where it’s failing, even though the speed sensors aren’t picking up any slipping. This will probably require a scanner with memory that can be played back/plotted or a trusted copilot since it will have to be done on the road.

You have a lot of miles on that box, good luck.

vesiadog

I know if it was my car I would be dropping the transmission valve body and replacing all 16 Orings on the solenoids. I have done it to a couple of 722.9 trannys. The older Orings get ripped and fall apart . There are a few sources to buy from .

JettaRed

iTrader: (1)

Mercedes will tell you that you cannot replace just the solenoids but must replace the conductor plate and valve body since they are "matched" from the factory. I don't know what that means, exactly, but it's the typical solution dealers use -- replace, don't repair.

But I do wonder if the solenoids that control the 1-2 shift weren't somehow damaged by the red fluid. Also, when the engine is cold, the tranny will drop to 1st gear even if in C/E mode.

raverx3m

its constantly changing lol
i never had a car with so many issues that are all design flaws lol
i usually buy hondas and they were all with 200-300k on them and have issues from being beat on extremely hard.but mostly fixable
this one so far every issue i had to fix was a design flaw rather sad when the manufacturer claims this great engineering and yet im dealing with manufacturer defects all the time

raverx3m

for last few weeks it got progressively worse. and now last few days it seems to be changing when it happens and how bad.
sometimes its not there sometimes it happens when transmission is warmed up and ive been driving for a while

vesiadog

The solenoids need a certain pressure but if the Orings are cracked the proper pressure cannot be reached.
I always replaced the solenoids in the same spot after replacing the Orings. Of course Mercedes does not sale the Orings alone they want to sell you the $100 solenoid . I also advise to clean the screens on the solenoids . If the valve body looks dirty you can also clean the valve body … there is youtube videos that show you how to disassemble and get to the passages and check valves.
If the transmission is an early 2006-2008 I would definitely look for codes and think about sending the board away to have the sensors looked into .. speed sensors etc.

JettaRed

iTrader: (1)

Seriously? You started this conversation admitting the car was improperly maintained by the prior owner. How is that a design flaw? Are you having other problems? What's your definition of "being beat on extremely hard"? Abuse? Neglect? Using a cheap mechanic that doesn't take the time to know what proper fluids to use?

Hondas are great cars and I have owned a couple in the past. But they are boring! And Honda's CVT trannies have their own long-term reliability issues.

vesiadog

You are going to lecture a guy about Mercedes 7 speed?? 😂 Yes they do have a lot of design flaws!
If you read enough postings you will find that trained Mercedes mechanics at Dealerships have put the wrong fluid in also.

Odd Piggy

A design flaw, like beauty, is in the eye of the beholder. A design flaw, in IMHO, is a component that fails before its expected lifetime. For Mercedes, that’s currently 150-160k miles - where the maintenance sheets stop.

When you take ailing ones apart, certain things wear out on Mercedes, others on GM, Ford, BMW, etc. Toyota and Honda probably have the longest lasting drive train components because of their extremely high volumes and the demands of their worldwide users. They play to their audience. When you’re used to a Honda, components that fail in a Mercedes make you wonder why they did it that way. When you get familiar with Mercedes boxes, the common causes become expected. Aftermarket parts suppliers have kits to make the internals of MB trannies “better.” They also have them for just about every other brand, too.

Recently read a post about how bad MB DCTs are. I’m currently running 3 of them and for my purposes, they are just fine. Opinions are just that, and everyone can support theirs with their evidence.

Let’s not argue. Let’s get this box fixed.

JettaRed

iTrader: (1)

I don’t think I mentioned Mercedes 7G trannies, but when something breaks because of negligent behavior, I objectively do not call that a design flaw. Use non-Honda branded and specified CVT fluid in a Honda CVT tranny and it will break just like a 7G tranny.

By the way, what are the design flaws of the 7G+ transmission? Maintain them properly and they are relatively bulletproof.

vesiadog

Just from that statement proves you have not been around mb 7 speeds… the 5 speeds were much more reliable.
Do some homework and then post. Am I going to make a list for you ?? don’t have time or the want !

JettaRed

iTrader: (1)

Then you are just blowing smoke. Since you claim the problems are so prevalent, I would think coming up with just a couple would be easy. Sorry that you mis-spoke and might have to do homework of your own.

I have been around early 7G and the 7G+ for quite some time. I've done my own tranny services and have removed the conductor plate and valve block, sent the conductor plate to CircuitBoardMedics and reinstalled everything. The early 7G was problematic as it aged. Mine started to have problems when it had over 100k miles and 18 years.

In the case being discussed in this thread, we know the wrong fluid was used. How long? Don't know. The OP stated the car has 195k miles on it. We have no idea how it was maintained up to that point. What was the word he used? Oh, yes, the car had been raped. That is neglect and abuse, not a design flaw.

raverx3m

you shouldnt have posted that
because right before i bought this car i had a 1996 honda odyssey van with 300k and the owner did exactly same thing.
it shifted rough i flushed the fluid and 3 weeks later it shifted like brand new and everything worked fine.
but since you want to argue about this
i have 6 mercedes in my family 4 of them are broken.
mine currently is the highest mileage one. all others have around 100k or less and they are parked most of the time because they are afraid to drive them too often.

i smashed on the c320 few times when it had 60k and all maintenance done at the dealer it already had slipping transmission. and like 3 new noises showed up after.
the other 2009 c300 also has transmission issues with 80k and is currently only driven around town
my e350 i had to fix the balance shaft and like 10 other things.

on the other hand.
i smash daily on my m37x with barely any maintenance for years it has 190k
i even smashed daily on that van with 300k nothing broke
i beat the **** out of my 4 cylinder b series hondas doing freeway pulls daily for 2 years because we had a very nice open chunk of road that was perfect for all 5 gears pull. and it still drives without issues( i know the guy i slod it to and he beats on it as well) without any issues still sold it 10 years ago.
i literally beat on every car i owned including the t100 truck i had that had 450k on it. one injector got stuck i replaced that and raced a mustang .

been doing mechanical work in my garage and i know few mechanics locally for last 20 years.

they all confirm this
american cars sound like **** and feel like they are half way broken but will run in that state for 50 years and still run
japanese cars will run whether you do maintenance or not. (i drove my honda with a hole in then block for 5 miles on 2 cylinders when i bought it)
german cars every problem somehow leads to catastrophic engine failure, need to be meticulously maintained to run .

alot of people here understand that. some people genuinely refuse to see the reality that german cars are designed to make money for a dealership.

japanese also design their cars to make sure dealers have something to do ( like honda exec admitting that b series engine oil pan gasket was purposely designed to leak because dealers would go broke if there is nothing to fix.)

the difference is. japanese car built in design flaws dont usually lead to catastrophic engine failure

raverx3m

jetta red. yes the car has been raped by the clown owner who plastidipped everything and couldnt even put the radio back in flush
he didnt do his mechanic work. he always took it to a shop
and there is a good history of maintenance it was bought at the mb dealership next to where i live. i saw the history and everything was done on time at the dealer until the degen mechanic in last 2 years.

on the other hand. there is no clear indications on what fluid to use.
this car is designed with many roadblocks for home maintenance.
starting with the stupid fkn atf fill hole and deleted dipstick
to oil pan dipstick running on top of transmission right fn next to where the old transmission dip stick used to be.
when i was replacing the balance shaft on my e class i lost count of how many roadblocks were built into it to make it more difficult to work on
but if you wannt to continue arguing i can spend some time and write them all out for you because i remember every single one of them where i was like wtf why is this bracket blockin the one bolt that i need to get to when it could clearly be routed 5 mm to the side and clear the bolt

JettaRed

iTrader: (1)

Actually, there is clear indication on what fluid to use if you know what you are doing and where to get information. Plug the VIN into www.lastvin.com and look for Code A89 REDUCED FRICTION. If you have that code, use the blue fluid. If not, use red. Seems like being on these forums for over 15 years, you would know that.

Just one question: Why do you buy Mercedes if you have these problems? Seems like you would be happier with Hondas and Infinitis.

raverx3m

I am happier wirh hondas.
and i still have my m37.
i bought this as a daily driver.

its not a clear indication when as mentioned by someone else here even mercedes dealers and mechanic shops put wrong fluid in it.

you keep trying to argue when there is mountains of evidence against you.
mercedes is not a reliable brand.
its a nice car to drive and i can see that you are a big fan and ignoring the facts.
i have no brand preference
i have a preference for good and reliable design
thats why i go with japanese engines usually.

JettaRed

iTrader: (1)

Look, you do you. I disagree there are "mountains of evidence" against me. I'm not ignoring facts, because none have been presented. You and vesiadog have shared your experiences, but they don't mean the whole brand is unreliable because you neglect and abuse your cars. I have two Mercedes currently that have been very reliable for me. But I don't smash my cars daily.

I just don't understand why you continue to own a Mercedes if you have such bad luck with them. Wouldn't you be happier if you got rid of your Mercedes and just stuck with a Honda minivan?

raverx3m

Year and mileage on your "reliable mercedes"

JettaRed

iTrader: (1)

2014 C350; 128,097 miles
2015 SL400; 48,887 miles

raverx3m

come back when you have at least 150k on both of them

50k and 100k is nothing

JettaRed

iTrader: (1)

Oh, please! I could have said they each had 200k miles and you would have said come back when they have 300k miles.

My 2000 Ford F150 has 230k miles and my 2004 Audi TT has 250k miles. Over the years, I've had to replace the transmission and starter on the Ford, and the steering rack and rear diff on the TT. That doesn't mean either have "design flaws". Parts wear out. If you beat the crap out of your cars, they will fail sooner. If you take care of them, they will last virtually forever.

Look, I'm not here to say who has the highest mileage. You're the one who came asking for help. I offered what I have learned over the years. And what I've learned is that there will always be people who complain about everything. If you really hate Mercedes, quit whining and get rid of all your friends and family Mercedes and go get some Hondas.

raverx3m

You wouldnt make it to 300k lol
i would be surprised if mine makes it past 200k
my m37 has same mileage owned by a drug dealer at some point and still better condition than any mercedes i owned with half the mileage.
you seem very butthurt that i said something bad about your favorite car.
mercedes has alot of good things. Reliability is not one of them.you can break yourself in half but it will never compare to japanese reliability