Originally Posted by maverik259

i had the same problem back around christmas...I took my car to a service station to just have them change the oil before my long road trip from FL to MD and about 150 miles into it i got the check oil level at next gas station...then 10 minutes later everything turned red and told me to immediately turn off engine and go to service station. I started freaking out that maybe they didnt put in enough oil or maybe th wrong oil, etc. So i finally get off the highway (keep in mind I'm in the middle of central FL which is like hick town with no major service centers, much less dealerships and it was a Sunday morning about 7 am). I went inside the station to look to see if they had oil, they only had 2 stroke and normal engine oil, no fully synthetic...i come out to my car and notice a puddle of oil under my car and my heart sank, i knew I was screwed. So i mad a risky decision, searched my gps for the nearest main stream service center who i knew would carry my oil and it was about 32 miles away and I was losing oil fast. So i made my way there, told them the problem and that it was their sister location back home that did the oil change. He brings me to my car 10 minutes later, tells me that they guys forgot to put the second o ring on the filter and then showed me the back of my car and how it was litterally soaked in oil. my entire undercarriage was dripping he said. Thank god for the heat sheilds b/c it kept it from reaching my wheels or rotors, that coulda been interesting to have slick rotors, lol... needless to say i received vouchers for 3 free oil changes and oil and considering these things run around 100 i figured that was a good enough apology for me !

Originally Posted by Karo

Thanks for the tips and info guys, I REALLY appreciate it.

I'll keep you guys updated on what they say when they call.

I hope it's something big so I can keep this car a little longer j/k

Originally Posted by Glyn M Ruck

However - downchange shift shock can most certainly be caused by software. It's all a timing issue on the second to first change & TC lock-up clutch release.

Originally Posted by Karo

I also noticed that when I downshift it goes low and has room to go one more lower (gear). Where my car goes low but doesn;t have room to go any lower. (this will go down one but mine will do down to the lowes tit can go (skips 2 gears instead of 1).

When I downshift on mine it goes above 5, but the rental c350 goes maybe 3 1/2 - 4 then still has room to go.

Keep you guys updated when I get a call from them.

By the way this dealer was Keyes Van Nuys and the SA's name is Donald Dorion

Originally Posted by holycaoAMG

Im a bit puzzled by this. My tranny jerks when shifting from P to D and has that downshift shock when entering a sharp corner while braking hard. My mechanic says it could be a number of things, and suggested it could be a simple software not being updated, i said no, and demanded a full flush done (getting it done this weekend).

Could my problem be a TCU software issue or does it just needs basic service on it?

Sorry for hijacking, just wanted to clearify.

Originally Posted by Glyn M Ruck

Holy - You have a 722.6 5 speed transmission like I have. It should be absolutely smooth - all the way up the gears & all the way down. It should not clunk into drive either. It is a well sorted old transmission. The 7G 722.9 like Karo's is still going through software upgrades by Benz.

I would start with a full flush & filter change & a software reflash. Also make sure the car is idling at the correct speed (not too high) & that the flex joints on your propshaft are in good condition.

When it jerks under hard braking - which change does it jerk on? 2nd to first? or higher gear?

On the 722.6 you can catch it out if you come off of hard throttle & brake hard when it's in the process of locking it's TC clutches. You need to drive pretty roughly to achieve this. Under normal driving it won't do this. Does this happen everytime you brake or only now & then?

Originally Posted by holycaoAMG

Im replacing filter, gasket, and refilling with ~10 qts of OEM ATF. (from pan/torque converter)
Car is idling at correct rpm, its pretty stable at 600 revs at idle.
It only jerks when i am under hard braking or hard braking as im entering a corner, when braking smoothly (which i do most of the time) it doesnt jerk or anything.
Jerk is from 2nd to 1st and sometimes 3rd to 2nd, and yes, i can feel it and hear it changing down.

I find it wierd, the transmission shifts smooth and fine when im driving hard and keep the revs high, but when im driving slow and it shifts at low rpm, its kind of noticable.

Shifting out of P to D is extremely noticable, my mechanic literally freaked out when he drove my car, it felt like i got hit from behind very hard.

Originally Posted by Karo

Thanks for the kind words guys.

One thing I noticed driving the w204 is it doesn't slow down as quick. On the w203 when I let go of the gas as it slows down I feel every downshift especially the 1st gear (sometimes it feels like someone slightly rear ended me). I think the problem might be the valve body. I looked at the w204 and for sure 2010. So I'm guessing they did major updates to the tranny (i remember on a thread the ML guys were saying how you can change the valve body and it wont downshift as aggressively).

Also when I put the car to drive the car jerks forward and the SA said that's a problem. Which the w204 doesn't have.

They didn't call me with an update yet so I'm thinking they haven't got to my car yet or they are still diagnosing it.

Glyn - Honestly after driving the w204 with it's flawless transmission I feel like I need a new car period . The transmission has not one jerk and remember how you said the 7-G should be like butter? We'll that's how the w204 is. You are right about the valve body. I feel like this is the main problem on the hard downshifts. Also the SA told me the torque converter when it goes out it makes a whining noise?

e1000 - ya it's weird. Every time I tap the shifter it goes to the lowest gear possible and always RPM is over 3. I think after they flashed the tranny software something changed (don't really know).

holycaoAMG - my car does the same. When I put it from P to D the car jerks forward (takes maybe 3 seconds before it gets into gear and jerks forward)

I'll keep you guys updated..Thanks again everyone

Originally Posted by Glyn M Ruck

Karo - There have not been any major mechanical changes in the 7G. It is a very simple transmission with all the complex old trouble spots designed out. Benz have learned from experience. Much of it's good or bad performance is driven by software/ fluid condition etc.

However - it should be like butter - that perception of lower engine braking on the new one is due to them allowing a little more slip everywhere & not being as aggressive with TC clutch lock up. All software driven. Our 2008 W204 350 is totally smooth & comes to a halt perfectly. It has all the software updates & I'm pretty sure that it comes to a stop in 2nd gear & then selects first for a pull away. I think Johnand feels the same way with his. I remember him passing a similar comment after updates in software.

You might have a valve body glitch - let's see what they find. It's not impossible that there are some updated valve body parts that I don't know about but early production 7G boxes can be perfectly smooth. At least you now know what it should feel like. Something might be damaged in your valve body or just sticky.

I agree with the SA that a whine will denote a failing TC but the more important issue with shift shock is not the TC itself. It is the behaviour of the TC lock up clutches.

Originally Posted by johnand

Glyn, is right. My 7G is very well mannered after SEVERAL TCU and ECU software updates. I am still fairly confident that a software flash should fix your 2nd to 1st issue, since mine did the exact same thing before a flash, and mine was one of the last 07's to come off the assembly line. Also, if you haven't done a fluid and filter change yet, I would go ahead and do that, because the new 4134 spec fluid really does make a difference as well. Early 7G transmissions needed a valve body change and software flash to fix the 2nd to 1st shift, but it is my understanding that all C-Class cars have the newer valve body, so just a simple flash should fix it. E1000 has your same model, and I remember his post about how much that latest software flash improved his 7G's performance.

Originally Posted by e1000

My car was one of the early 2006's so when I first got the car, it had some trouble shifting. It's always had the 2-1 shift issue, but just before 30k, it had a problem from 3-4 and 4-3. Fortunately I knew my SA well and he replaced the valvebody and did a full transmission flush under warranty. The 2-1 shifts are a lot smoother now and 3-4 or 4-3 is never an issue. Actually, other than slowing down and going from 2-1, people swear I have one large gear.

Originally Posted by LILBENZ230

The valve body issue is the same that afflicts the 2006 MLs, I guess?

Is the new 4134 spec fluid good for the 722.6 or is it specifically for 722.9?

Originally Posted by Glyn M Ruck

Karo - There have not been any major mechanical changes in the 7G. It is a very simple transmission with all the complex old trouble spots designed out. Benz have learned from experience. Much of it's good or bad performance is driven by software/ fluid condition etc.

However - it should be like butter - that perception of lower engine braking on the new one is due to them allowing a little more slip everywhere & not being as aggressive with TC clutch lock up. All software driven. Our 2008 W204 350 is totally smooth & comes to a halt perfectly. It has all the software updates & I'm pretty sure that it comes to a stop in 2nd gear & then selects first for a pull away. I think Johnand feels the same way with his. I remember him passing a similar comment after updates in software.

You might have a valve body glitch - let's see what they find. It's not impossible that there are some updated valve body parts that I don't know about but early production 7G boxes can be perfectly smooth. At least you now know what it should feel like. Something might be damaged in your valve body or just sticky.

I agree with the SA that a whine will denote a failing TC but the more important issue with shift shock is not the TC itself. It is the behaviour of the TC lock up clutches.

Originally Posted by e1000

uh, heh, I actually had my transmission flushed and my valve body replaced at around 30k miles.

Originally Posted by Karo

Yup today when I was slowing down I noticed that the w204 doesn't stop in first. Remember how I told you I took a turn going 40 and pressing the pedal all the way and lost control and barely made it? After this when I would press on the gas it would lagg couple of seconds (3-5 seconds) then change gears. When they flashed it it wouldn't do the same but the tranny was never the same.




My car was built November 2005 and has 32K miles. So I'm assuming since it's an early 7G it might have some issues?

But I will keep you guys updated when I get a call from them.