Transmission Wouldn't Shift
 

I was on vacation last weekend and after we'd been driving for an hour the transmission would not shift. It seemed like it was stuck in 3rd gear. Wouldn't go up or down, I tried doing the manual shifting with the steering buttons but that didn't work either. Once I turned the car off and restarted it the car seemed to be fine. Anyone else have this problem? No warning lights came on.

We had the same problem, it was stuck in first gear. Shut it off and worked fine after. Later on the dealer replaced the valve body. Now 1st shift of the day is longer than normal.

Could you guys include what year your GL is in your profile? (Or in the messages?) So we who own them can either sweat less (different year) or more.

Thanks!

STP

Mine is an 07

07 AS WELL.

Same problem, normally stuck in about 3rd. Only way to fix was to pull over, shut down the vehicle and restart. We have early '07 450 - Built in Aug 06. Started about 30k, same fix - replace valve body. Only problem we have had, we are at 48k now.

Okay, I don't see anyone with an '07 320. That means mine should break down in about an hour.

Whle we're speaking about '07 GL450, does anyone have a howl-whine on acceleration from stop and starts @ 2000-3000RPM? Dealer says it does not exist but it's there! My friend has an '07 and it's quiet.

I have a c240 2002 and it happens when I go to work about 4 in the morning. Its usually cold and the gear jerks when it going into drive. The car stays in first gear and doesn't shift automatic. When I turn the car off and on again it works fine. I changed the crank shaft sensor recently but dont know if its related. My light sensor visit workshop message comes on periodically and I plan on changing my battery soon since I hear it may be related. I also plan to get a code from the light sensor message since I hear its a stored message. I just know that I dont plan on visiting the stealer anytime soon. The repairs on this car has become my part time gig :bow:.

it happened with mine frequently , some times in 1st and sometimes in the 3rd and i have to switch off then it is ok. When the problem happens , the gear indication in the instrument cluster show nothimg or showes P eventhough the stick already in D.

What is valve body , where it is located , how it is related to the gear functions? any one can help
Thanx in advance

Valve body is usually bolted to the bottom of the transmission and has all the vanes and little spring loaded ball bearings which allow the fluid to pass through. This is what controls the shift pattern. When the gasket between the valve body and transmission base fails, you sometimes have fluid loss from the small vanes which yield the shift issues. Hence, usually, dealer either replaces gasket or entire valve body depending on issue. All of it is done by opening the transmission oil pan below the vehicle.

Hope this helps.

Gear stuck in 1st or 3rd with no or wrong indication in Ins. cluster
 

Thanx alot Nynd , its realy help.
It seams that valve body does not contributes to my problem since that valve does not send a signal to transmission controller or to the I.cluster indicator , why ;because the problem takes place only when there is no indication at all or wrong indic.in the I. cluster(e.g. showes P while the G. stick already in D ) . The signal comes from the gear shifter . Do you think the sensor in the G. shifter module is mulfunctioning , I recall once carrot juice was spilled on the module,does that effect?

I have it too - 2007 GL450 - seems to be coming from somewhere in front of the passenger side of the engine. Same story in that the dealer said he could not hear anything that was not normal for the car. I'm hoping they are right :-0

gl450...
 

I had the same problem on my GL450 2007, I brought it to dealer and they said they have to keep the car for testing to replicate the error before fixing it. It was stuck in the 1st gear, but there was no warning msg or whatever error on the dashboard.

Did you car pop up with warning message? error codes??? in order for them to change the Valve body??? Please let me know...
Thank you..

I never had any error codes. After I changed the battery everything was normal again. Transmission was automatic again.

07 gl 450 stuck in gear
 

i just got mines back last week. it had the same problem it would stick in 1st gear or 3rd gear. the dealer had to replace the vavle body total was $1800.00 good luck.

Same problem with my GL450 2007 , 55K miles, I brought it to service on Nov 21, till today Dec 6 they called and said they will replace Electronic module Control (Not Valve body). They are still waiting for part. it may takes up to 2 weeks to have part. I don't know it going to be the right fix or not...
I'll let you guys know.

The mb dealer tried that part on mines, but that didn't fix it. So they change the valvebody and that fixed it. You might wanna tell the shop fixing your car that most 07 gl450 that had problems with the transmission not shifting had to have there valve body replaced. My vehicle was at the delearship for 3-4weeks.

I did tell the dealer and MBUSA center, but they will change "conductor Plate" according to the "error code"....
I dropped the car on Nov 21...today Dec9 still waiting for part...will update more.

Thank you....

722.9 Transmission won't shift - Contact Plate - Help!
 

Is Mercedes covering parts and/or labor to make the required repairs?

Here's what I've found out. Please pardon me if any of this is a regurgitation of an earlier post or posts.

I understand that late model Mercedes 7-speed transmissions have the electronic control unit mounted inside the transmission, and that these control units are failing more than frequently with speed sensor codes (the codes usually relate to speed sensor faults). I also understand that the speed sensors are not replaceable as they are part of the electrical conductor plate that bolts to the valve body inside the bottom of the transmission. I hear rumblings that Mercedes and Siemens VDO are battling over whether the control units are fit and sufficient for the purpose intended or rather are bad product.

In addition, I read that the units are failing so often that, to order a part, dealers must submit a request with computer scans and control unit log reports of the suspected failed vehicle's electronics - and that the factory then sends the parts they deem necessary for the repair. So it sounds like the manufacturer may be covering the cost of these parts - albeit reluctantly. Furthermore I hear that people are waiting 2 - 4 weeks or even more for the dealer to get the repair done due to the part lead time.

The last thing that I found was Mercedes Service Bulletin S-B-27.00/120 dated April 8, 2011. This bulletin lists multiple prior Service Bulletins, as well as replacement parts, replacement parts for replacement parts, and replacement parts for replacement parts for replacement parts for Mercedes Models equipped with Transmission 722.9 including model 251 (mine). It is clear to me that Mercedes has a serious product defect problem, and it appears that they have circulated this information to their dealers on the sly and are carrying out replacements without any acceptance of blame. They should really have a recall and not just a service bulletin as life safety is a real concern where transmission failures are concerned.

I have been quoted $500 for the part and $700 for the labor. What are you all paying? Is anybody getting help with this from MB and/or their dealer?

Thanks for listening - and thanks in advance for your reply. I do not want to replace defective product at my expense. I especially don't want to replace one defective part with another.

Thanks and regards,

""""""It is clear to me that Mercedes has a serious product defect problem, and it appears that they have circulated this information to their dealers on the sly and are carrying out replacements without any acceptance of blame. They should really have a recall and not just a service bulletin as life safety is a real concern where transmission failures are concerned."""""
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b/c it's a brand name auto maker, that's why they don't accept this type of problem, and don't want the world to know the recall...:crazy:.....

Mine did it tonight. Shut off/ restart cured the problem. MB needs their feet held to the fire on this one; a 65k truck with 60k miles shouldn't have this issue. My truck doesn't have a hitch, so it has never towed anything.

I have been quite happy with mine so far; but this would certainly be a deal breaker.

It seems like an electronics/control issue, since power cycling it seems to temporarily solve the problem....

More info needed before I go on a tear with MBUSA...

And what makes it worse, it will nag me if a marker light is out or even better - someone gets in and out of the front passenger seat and the airbag is switched on and off - (annoying!!)

- but it makes no mention or warning of "you are stuck in low gear, 5k rpm is NOT cruising speed" - really?

UPDATE
 

MB replaced "conductor plate", Now the truck is shifting smoother with about 1K miles...will update later around (6K miles)

My 08 had warped plates(?) inside the transmission that required pulling the transmission and opening it up to repair. It was holding onto first gear too long and then shifting abruptly when it did. I'm glad the car was still under warranty. It would not have been a cheap repair.