Mercedes-Benz Forum banner

For those that have the rough 2-1 downshift in "S" mode

101K views 67 replies 30 participants last post by  MB 1991 300SE 
#1 ·
MBUSA has just released a new valve body for the 7G transmission in the R-Class. I had my R500 in for service and they swapped mine out. The transmission has never shifted so smoothly since I've owned it. I can keep it in "S" mode all the time now and never feel it downshift into first when coming to a stop.
 
#2 · (Edited)
B-O-R,

Thanks for sharing the info. When did you have this done? Can you provide more info on the newly released "valve body"? Is this to cure the "downshit" feel of engine braking coming to a stop? I have a couple of software upgrades done and they cured the "jerking" for "upshifting" from 2-3 in the 20-30 mph. The car shifts up and down very smooth, except for coming to a stop. I do feel a "squeeze" of engine braking in the last 10-20 feet prior to a stop and has been thinking it is normal until I read your post. If possible, please type/post the diagnosis of symptom and work description completed from your service ticket. Thanks in advance.

BTW, do you use EMC in Germantown? I bought my car from Germantown but always take my car to EMC in Bethesda.

Loc
 
#3 ·
Yep, I take it to EuroMotorcars-Germantown. The shop foreman, Jeff, is very familiar with me and my fleet of MBs. They've gotten to know me very well there, unfortunately.

But yep, it has completely solved the rough 2-1 downshift. The car literally feels like it's in neutral coming to a stop, it's that smooth now.

This is taken directly from my service sheet:


...Replaced electro hydraulic valve body per WSG Case 710131492. Performed SCN coding and learning process after repair. Road test to adapt transmission.

Here are the parts listed:

(1) 220-270-21-06 Valve Gear
(12) 001-989-45-03-13 Transmission
(1) 007603-012102 Ring, General
(6) 004-990-35-12 Screw
(1) 220-271-03-80 Gasket

274989 Valve Body - 722.9 Trans-R&R
271256 Oil Level - Auto. Trans (After Leak Test) Check/correct
271047 Adaptation, Perform (After Repairs)

I know the parts and task list can be a little cryptic but it looks like they replaced the valve body, checked the tranny for leaks and fluid level. Then reset the adaptation.

The shop foreman told me that MBUSA wouldn't allow them to put in the new valve body in the past but now they are for some reason.

Hope this helps. I can tell you that the car has never shifted this smooth, ever.
 
#4 ·
This is taken directly from my service sheet:


...Replaced electro hydraulic valve body per WSG Case 710131492. Performed SCN coding and learning process after repair. Road test to adapt transmission.

Here are the parts listed:

(1) 220-270-21-06 Valve Gear
(12) 001-989-45-03-13 Transmission
(1) 007603-012102 Ring, General
(6) 004-990-35-12 Screw
(1) 220-271-03-80 Gasket

274989 Valve Body - 722.9 Trans-R&R
271256 Oil Level - Auto. Trans (After Leak Test) Check/correct
271047 Adaptation, Perform (After Repairs)

The shop foreman told me that MBUSA wouldn't allow them to put in the new valve body in the past but now they are for some reason.

Hope this helps. I can tell you that the car has never shifted this smooth, ever.
This is GREAT! :thumbsup:

Thank so much for sharing. This is helpful to a lot of us. :bowdown:
 
#13 ·
Difference between "jerky upshift" vs "rough downshift"?



Chucelli - Not yet but I will when I bring my car in for the Service A at 10,000 mile (in a month to two). I'll post afterward.

Chucelli / or Anyone - What have you experienced with the "rough downshift to 1"? Does it happen all the time? When it does, is it "mild", "medium", or "hard"? Mine is very "mild" and happens 25% of the time (coming to the stops), which makes me feel that it is "normal" until I read/saw BenzOrama post.

For jerky up shifts of 2-3 or 3-4, going uphill at slow speeds, I have had 3 software updates (at 800 miles, 2000 miles, and 6,800 miles). Those are gone, and up shifting is very smooth except for very occasional jerks (once in evey 2 to 3,000 miles).

But this jerky "upshift" from 2-3 I assume is different than the rough "downshift" from 2-1, coming to a stop. And, I plan to take it up to the SM for a "valve body" replacement, based on BenzOrama advice.

Anyone with either upshift/downshift experience, please share.
 
#6 ·
great news....i wonder if they tried that valve body...they tried two before replacing the entire tranny in ours...now we have negotiated the transfer to a 2008 r320 to replace the 2007....we pick the new car up tues
 
#8 ·
there is no "newly released" valve body for the r class. updated valve bodies have been out for years for every new MB model. usually all MB models will come with a 1206, 1306 or 1406 valve body. updated valve bodies are usually a 1306 for the 06 and older e class as a 1806 is for newer mid 06 and 07 e classes and newer. new s classes and most other mb models require a 1806 or 2106 valve body. if you still have trans issues and you have the most up to date valve body and trans software and the problem cant be fixed, MB will approve the replacement of the trans.

now 9 times out of 10 a new valve body will correct the rough 2-1 downshifts. trans software updates are like a band aid. they cure it for a while.
 
#9 ·
Whether it's a newly released valve body or not, the shop foreman at my local MB dealer stated that MBUSA has just started allowing them to replace these valve bodies with an updated one. He could've been misinformed, or just plain making it up, I don't know. But I can tell you, with 100% certainty, that my R500 has never shifted so smooth since they replaced mine. You can't feel the 2-1 downshift at all anymore.


I would suggest to anyone having this problem, to print my post above and take it to their dealer.
 
#10 ·
MBUSA has allowed for valve body replacement for years. as long as its approved by WSG, there is a form that team leaders or shop foremans fill out on netstar that requests a valve body or trans replcement on a vehicle. you give MBUSA the vehicle info, issues and what has been done. you get a yes or no answer. now most of the time, techs will just flash the trans control unit. usually a valve body get requested after several complaints or when a fault is stored in the tranny. 99% of faults that occur in the tranny require a new valve body.
 
#11 ·
I hear ya...

I guess that's why they had to state the WSG case on my worksheet. What the hell is a WSG anyway?

Thanks for the info.
 
#14 · (Edited)
RDriver,
I feel my 2-1 downshift every time when stopping but I would say it's "mild", meaning right before reaching a complete stop, it will feel like all the sudden the car breaks harder for the last 10 MPH or so. If I brake VERY gently, to the point of almost riding the brakes, I can minimize that feeling of the 2-1 shift.
Other shifting anomalies I've noticed are very harsh shifting at certain times when I let off the throttle gently after a hard takeoff (or going up hill). I haven't yet been able to reliably reproduce that behavior however...
It may be the jerky upshifts you seem to be experiencing.
hope this helps.
 
#15 ·
also a rough 2-1 downshift doesnt necessarily mean you need a valve body or software update. adaptations have to be checked first because if your b1 and b3 clips have come apart in the transmission, it will cause a hard jerk right before you come to a stop. E classes and ML and R classes have been the most common cars that i have replaced clips in.
 
#16 ·
Does anyone get the rough shift from 1st - 2nd? I occasionally get the downshift from 2-1 but not enough to bother me. But what I do get is rough shifting from 1-2, its like 1st gear shifts too early. The rpm's only go to about 2000 rmps and than shifts to 2nd. This also affects acceleration because 1st is not getting drawn out long enough and I am loosing the powerband. Has anyone experienced this, if so does the updated sofware help?
 
#17 ·
Oh Yes



Rough 1st 2nd is very common. Especially after software updates. It dove me crazy. I had a few trips to the dealer for that. I had to bring it to another dealer where the tranny specialist had to update both the ECU and Tranny software. I still feel it a bit but it is almost gone. The more you drive it the better it gets.
 
#18 ·
I spent a lot of time researching this issue. There is a software update that fixes these issues but it works only on the newer valve body. In other words if you have the old valve body you cannot use this current software version.
 
#20 ·
I was told that if you have the bad older valve body you the car won't take the newest software version.
 
#22 ·
I took my R 320 CDI to get checked with the valve body checked. The dealer confirmed that Mercedes is replacing faulty valve bodies. Mine 2007 had the most current valve body and software. Basically if you do not have the most current valve body you cannot have the latest software version installed. They double checked my car.
 
#24 · (Edited)
I still do not understand what valve body they installed in Benz-O-Rama's car.
My car is '07 production date 9/06. Can they put the newest valve body that is designed for the 08 models in my car and latest software 01/2008 to further improve shifting quality...
 
#25 ·
i had the same exact thing benz-o-rama had done and it is really shifting smooth. I had more of a rough shifting from 1-2 and occasionally the downshift from 2-1. Now it really shifts silky smooth. I printed out a copy of the tread with benz-o-rama's service a
sheet and they looked at it and just had to gey approval. Now if i can get around paying $34 a day for a Sonata. Lol ! Does anyone know how long it takes for the reprogramming of the trans to adapt to my driving habits and locked it in ?
 
#26 ·
Sweet! Mine is still as silky smooth as the day I got this done. It shouldn't take more than a couple of hours to do, once they start.

The adaptation doesn't really 'lock-in' to your habits. It is constantly adapting to whomever is driving. But, after they reset it, it shouldn't take more than a day or two to adapt. That's a complete guess though.
 
#29 ·
Actually sitting at the dealer now for a inconsistent downshifting jerk (when slowing down to a stop - for a stop sign, etc.).

Of course the tech and I went out and it wouldn't do it, but both my wife and I have felt it.

They're currently checking the software on the computer and checking for fault codes.

I'll ask them about the valve body in a bit.....
 
#30 ·
I just called my dealer and am taking mine in Friday to get the software checked. I'm also taking this posting info to show them. The downshift is really anoying, but mine only happens when i drive downhill leaving my home.

I cost to the stop sign at about 20mph and touch the brake very lightly, then BAM! It is driving me nuts.
 
#31 ·
If it's only downhill, it's probably something different. There is another problem where a certain ring in the transmission was not installed during assembly. The lack of this ring causes premature wear and rough 2-1 and 3-2 while doing downhill. Have the dealer pull the pan and check for metal. If there's no metal they'll install the ring, change the fluid and you should be go to go. If there's metal, you get a new tranny. :D

This came straight from a current MB tech that I talked to.
 
#33 ·
I've got a 2006 e350 that went into service in Aug 2005. Recently I encountered a couple of incidents where I was at a stop light (tranny in C mode, starting out in 2nd) and when the light turned green, I pressed the accelerator and got the RPM's up to 2000 before the car would even move! I took it to the dealer and of course they could not reproduce the issue but they did check the tranny for codes and found code 2204 in trans and in ME control unit code 1785. They subsequently updated the software in both trans and engine and I haven't seen the hesitation problem again, yet. It is a 722.9 tranny. I been hearing alot of talk about valve body replacement but the service advisor says that unless they can reproduce the problem or pull a fault code from the tranny they can't just start replacing parts. I felt this issue was rather frightening. Giving the E gas and she's not moving as if she were in neutral. Well at least if it happens again I can take it back under what's left of the original warranty and CPO warranty. The tranny does feel 'tight' when downshifting from 2nd to 1st in S mode, not sure if that is symptomatic of the valve body problem also.
 
#34 ·
Similar experience with my 07 Diesel. The tranny felt loose clanking rough etc., took many calls to customer service before they did put a new valve body and a new clutch. Even then it was still jerky...
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top