zenocchio

I just picked up a 2011 E350 4matic wagon, from the original owner. It was serviced all its life at the dealership, the last major service was just done in january. The car has 135,000km or 83,000miles.
At any given speed, and gear, with light and steady throttle input to maintain speed, at around 2000RPM the tach fluctuates around +/-200RPM. Its not a tach issue, as I feel the vibrations and hear the change of tone in the exhaust. At first I though it was related to spark plugs/injectors, as it felt like a missfire, but the plugs were just changed. Now I am leaning more towards the torque converter or transmission, but surprised that I have issue at such low mileage.
Any recommendations on how to start to diagnose? Unfortunately I don't have access to a Star software but just basic obd scanner (any recommendation for a good one?)
thanks!

bmwpowere36m3

Sounds like the exact same issue as this guy and his resolution appears to be a replacement torque convertor and rebuilt transmission: https://mbworld.org/forums/e-class-w...ml#post8286758

With a basic scanner I think our SOL, for lack of a better term. Really the only thing you could do, is R&R the fluid and filter. While the pan is dropped, look for signs of debris and pay attention to the magnets... and anything stuck to them.

Are there ANY codes your reading?

Fliplegend

Has the motor and trans mounts been replaced?

Arrie

I have iCarsoft MB II scanner that reads different speeds in the transmission and TC. It even tells you if the TC clutch is slipping.

In my E550 it gives me this message because the speed readings differ a few tens but I think it is inaccurate speed signals causing it as car works perfectly with no issues at all. If you have engine speed changing a couple hundred revs you will definitely see it with this scanner.

This scanner only reads. You cannot do programming with it. It cost me little over $100 thru Amazon.

There are much better scanner tools available but this is low cost for data reading tool especially for pin pointing your issue as TC or transmission itself.

bmwpowere36m3

It indicates the TC is slipping when it shouldn't? These TCs will slip in certain ranges and that's normal. The TCU relies on the speed signals within the trans, so either you believe the sensors are bad or your scan tool isn't accurate?

If you have a scan tool that can force a lock-up (Xentry can)... that will help in further diagnoses.

Arrie

I don't think the scanner reading is bad. It is either bad signal from speed sensor(s) or the clutch actually slips a little bit. It does the same on my S550 so I'm not worried about it. Everything works fine.

bmwpowere36m3

There seem to be, at least, two different TCs for 722.9 transmissions, with and without centrifugal pendulum damper [Fuel Economy, FE, torque converter]. The latter can produce more lock-up, but not 100%... "use of a centrifugal pendulum damper, it is possible to reduce the slip at the torque converter lockup clutch to a few revolutions per minute"

The latter doesn't seem to apply to M272, M273 nor M276 engines (not sure what a M276LA is) below. So in the case of M272, M273 and M276 the TC never fully locks-up, its either open or slipping.

bmwpowere36m3

From older 722.9 doc (circa 2004):

zenocchio

Thank you all for your reply.
I was looking at my build sheet and noticed that a 427 code for the amg MCT-7 speed sport transmission. If I’m not mistaken that one doesn’t have a torque converter. I have paddle shifters.

my vin is WDDHH8HB8BA513726

what transmission do I have in my car? 722.9 or the MCT?

zenocchio

I don't have any records of the engine or trans mounts replacement. The full front end suspension was refreshed, including wheel bearings.

KEY08

you do not have a multi clutch transmission in your wagon. That’s not right unless it is an AMG wagon, and I don’t mean an AMG trim package.

bmwpowere36m3

Both our '11s have the same code 427, "AMG SPEEDSHIFT MCT 7-speed sport transmission" and 428 "DIRECT SELECT shift paddles" per EPC data card. Their just the plain 7-speed 722.9 with E/S modes and paddle shifters to restrict or de-restrict the gear "range" .

Seems misleading...

zenocchio

awesome, thanks for clarifying that. So this tells me that I have a torque converter. i am wondering if that is the cause of my issue.
the previous owner had it checked at a shop and they thought it was the intake flaps, but i have no codes.

bmwpowere36m3

Sticking intake tumble flaps will generate a fault code, before eventually the mechanism breaks. You should be able to manipulate the mechanism with your finger: https://mbworld.org/forums/e-class-w...ml#post8282782

Left Coast Geek

all US model 212's have the AMG 7g+ 'speedshift' transmission, even the elegance/luxury models... only the actual AMG cars have the HCT version that has a double clutch, the others are the MCT version with a torque converter and torque lockup clutch.

zenocchio

I just scanned the car and found two codes stored P1369 and P0521. I used a generic scanner so no details are provided.
not seems that P0521 is related to the intake flaps. That kind of make sense.
I did further testing and realized that the RPM fluctuation happens at around 2000RPM with steady low input throttle but only when the car is in gear and I can’t replace the it when in neutral. Any thoughts?

zenocchio

My indie mechanic check the car over and took it for a spin. The verdict is the it needs a new transmission. The fluid is dark and they found some metal shavings. They suggested a rebuild for $3-4k.
I want to make sure that the intake is ok before proceeding with the trans replacement so I will just get a repair kit for the intake flaps.
I expect that this trans is common in the mb world, do I need a 4 matic specific one or any w212 trans will work? What is the part Nr?

bmwpowere36m3

If you bought a non-4matic 722.9, then you'd have to swap over the transfer case... assuming that's possible. 4matics are common enough, but realize the transmission module (TCU) is "married" to the car. Officially, you need a new conductor plate/TCU which will need to be SCN coded with appropriate equipment. Or you find a someone who can "wipe" the old TCU and recode it. Or transfer over the "old" conductor plate with all the solenoids.

Just make sure, whoever is doing it... can.

Left Coast Geek

722.9 is just the transmission family, *all* 7G transmissions are 722.9

per your data card according to your VIN, you have transmission 722.960 ... I believe this is the 7G+ MCT 4Matic mated with E350's, both M272 and M276.

Transmission model/serial: 722.960 03563368 part number: 2122704103

re: swapping the transfer case from a non-4matic trans to a 4matic trans, that would be a good trick, because the 4matic transmission has a longer housing with the transfer case integrated into it.

nc211

I would change the fluid and filter and maybe clean the solenoid plate while in there before I would replace it. Since the fluid is dirty, that alone could be the problem.

Mine has a little flutter too when I’m cruising down the highway at say 80mph, very gently press the gas, and the rpm will wiggle up maybe 50-100rpm before speeding up the car. I just think it normal as part of a torque converter process. There is fluid between the engine and the gear box after all, it’s not a direct bolt, so some give is expected. Since your fluid is dirty, I’d just start there before sinking $4k into a 10 year old car. I’d also replace the two motor mounts, trans mount, rear diff fluid too. That will tighten it back up to new feeling overall. Maybe even grab the flex discs at the ends of the propellor shaft too.

I would not be sold on needing a new transmission though over something like this. Just too many other normal wear and tear items to look at first - with the main one already proven to be needing attention - the fluid!

bmwpowere36m3

I agree with @nc211 I'd go for bust...

• drain the TC and transmission
• drop the valve body
• separate the valve body to clean all the passages and check valves
• clean the solenoids
• flush the transmission cooler
• clean transmission pan
• replace filter and fluid

Maybe $150 in materials and labor, yup it's a little involved. Ultimately the debris came from somewhere... at best you caught it early enough and a cleaning/flushing will resolve the issue. Worst case, it doesn't resolve issue or the "fix" doesn't last long.

nc211

Also, OP - let this one be a reminder, just because it’s a MB Dealership, does not mean it was done or treated right. In fact, I don’t trust a MB dealership period. I have never seen such BS in all my life than from the service department of now 3 different dealerships. Personally, I think the service department is aligned to the sales department and the last thing they want to do is fix it for $500 when that $500 could mean a new car deal to replace it instead. But that’s just my own opinion. I own two MB’s these days. One under warranty, one not. Even the one under warranty doesn’t get its oil changed at the dealership and never will. Not because I’m cheap, but because I just don’t trust them. On my w212, one dealership actually sheeted off a bolt to the transmission pan itself and just covered it up. Also charged my tire warranty company $800 to fix two bent rims when in fact they never even touched the bent rims to begin with, kept my car for 10 days, and assured me it was fixed. All I got from that visit were scratches all over my trunk from their dumbass installers trying to re-attach 2 inches of the read deck lip spoiler that had come loose. Prompted me to download Yelp and leave a barn burner review for Tysons Corner Mercedes Benz (screw you guys, if you’re on here too)! I could write a novel about the absolute abysmal service I’ve gotten from a MB dealership. Brake fluid change = dust plate scraping a groove in my new rotor. Seat repair = broken seatbelt latch. Tire repair = replaced with a defective tire, and so on and so on. Just...don’t. Next time you’re at the gas station and see a nice looking older MB, kindly ask the person who takes care of it for them, and then go there..

Need an example? Read your first post, and then read your other post about needing a new transmission. Fluid dark brown. At 83,000 miles and “serviced at the dealership all its life”, should not go together. Chances are (very high probability) you’re on the original fluid from 2011, which should have been replaced about 20k miles ago. When mine was drained at 48k, it still had strong hints of red, the original color.

given this info - transmission fluid has a viscosity purpose. I am very much leaning towards just needing a good flush, new filter and new MB fluid. And not a new transmission. It costs maybe $500 to have done, Max. Or do it yourself if you’re capable to.

Who sold you this car? Was it off a
MB dealer lot?

zenocchio

I purchased from a soccer mum, original owner. All maintenance was done at the dealer while under warranty and at an indie afterward. oil change every year, a lot of maintenance done.
I am going to replace the intake actuators, and see if that fixed my surging problem, and then will tackle the transmission, starting with a flush as suggested.
I actually had the car checked out by three mechanics, the first one was the shop that dealt with it most of its life, and they diagnosed the problem as intake runners. then I went to a mercedes specialist, family run old shop in town that deals with old mercs, and they said its the transmission. they recommended a transmission shop as they don't work on trans. the third shop (recommend by the second one) confirmed it as trans issue after taking it for a spin with a computer connected to the car. they were not able to pinpoint the issue and said that they would take it apart and replace whatever is out of spec.

zenocchio

Quick update, I replaced the broken intake actuator arm. While this took care of the intake related fault code it did not fix my stumbling issue.
I feel that the transmission is slipping more day by day.
I am debating if I should spend 200$ and try flushing the fluids or go directly to a rebuild.

zenocchio

I got a second opinion from a reputable shop. he confirmed that the torque converter is failing and needs replacing. He quoted me 2K for trans flush, new torque converter and solenoid but recommended to do an overhaul to make sure that other components will not fail in the future for 3.5k. what is the general consensus here? is the piece of mind worth it? what are the chances that other clutch disks are going to fail?