jiifamily

Hi all,

Not sure if it's really an issue but i am bothered by this transmission behavior since day 1 i got the ML350 BlueTec. (Currently has 1000 miles)

The transmission, will rev up for around 300~500rpm, when shifting from 3rd to 4th gear, especially when the engine is cold. *this won't happen for all other gears, and it happens during normal driving.

i.e. car will shift from
1st to 2nd at around 2200rpm, dropped to about 1900rpm, then shifts from 2nd to 3rd at around 2200rpm, dropped to about 2000rpm, then, when i hit 2200rpm on 3rd gear, the car will rev up to like 2600, while shifting into 4th (drop to about 2000rpm).

It feels like when i drive my old 08 Civic manual, didn't let go the gas when i step on the clutch and shift, (yes, that drive by wire system does often create some rev hang issue), but i am talking about an automatic here.

If i drive more aggressively, like put more gas and let it shift at around 3000rpm, it won't be as bad, but i can still see the needle goes a little bit higher when it shifts from 3rd to 4th (+100 to 200rpm)

However... once it's at 90degrees Celsius, problem seems to go away. Perhaps that's what it supposed to be? Just that it only happens during 3rd to 4th gear change makes me wonder.

Thank you for reading this long post, but all my previous automatic cars (Lexus, Toyotas, Hondas, Acuras, even my old 05 C230), do not have this kind of issue.

I could do a youtube video if i need to, let me know if i do not describe the issue clear enough.

Thanks...

Vernl

Your manual tells you to let your vehicles come to normal operating temps before any ''aggressive'' driving.The fact that your ''problem'' disappears when its warmed up speaks for itself.

jiifamily

Thank you for the reply, and that's actually where the issue is... i expect it to don't rev up when shifting from 3rd to 4th during normal driving warm or cold.

Now i kinda recall that i had an old 1990 Acura Integra auto that would rev up during 2nd to 3rd shift constantly, but that was a transmission problem (slipping 3rd gear)

I guess it's not a big deal and i have to just live w/ it... perhaps i could go test the other bluetec at the dealership during my next visit. They still have quite a few in stock.

I'd like to hear about it from other bluetec owner...

thank you

davatk

Greetings - Not sure if this is the same issue, but I just got a 2011 ML350 Bluetec and I have noticed early in the morning that when downshifting that I hear a bit of a clunk. Seems to go away after about 10 minutes of normal driving, but it is a bit irritating to hear a clunk from the transmission shifting on a brand new vehicle.

aggst1

+1 on letting it warm up and then question its shifting and also since your car is so new , be advised that it is constantly adjusting shift points based on your driving habits. So give it some more time.

davatk

Thanks for the info. I forgot about that - the adjustment that the computer makes for your driving style.

Stesl

or turque converter that slip while changing in 4th gear or auto adaptiation...wait another 1.000 miles and that tell us how it behaves

davatk

2000 miles and still happens.....

Stesl

go to the dealer, ask them to connect it to the diagnosis, it's absolutly not normal, my ml did it from 2 nd to 3 rd gear...update also the software of the 7g tronic if possible

dgiturbo

Back in 07/08 they had issues with the software and valve body/computer unit that would cause the issues you are all describing with the diesels.
I thought they rectified that as no one has been complaining for a few years now. Looks like they may have gotten another bad batch of valve bodies again.
The slipping between 2-3, the downshifting 1st gear "clunk" or the feeling you got rear ended right as you stopped for the first stop sign in the morning were all fixed by
1) software reprogram
2) reset adaptations
3) replace valve body and refill with new spec fluid.

By now all the dealers should be experts on diagnosing and repairing these 7G issues, so get it to the dealer ASAP before there is more damage.

Stesl

quote 100%dgturbo

C43AMG

Just had mine flatbedded last night for transmission failure - 410 miles left before warranty expired !

n1smo

I've noticed the transmission doing what you described once in a blue moon. The vehicle was definitely warmed up and I was not driving aggressively. I don't think its a big deal but please keep us posted if you find out anything.

michaeloliverio

I have a 2011 bluetec also. 2900 miles so far.

I am getting same slip/rev 3 to 4 gear only when cold. Goes away when warm. Will continue to watch and check with dealer in another month or so

primatives

i have the exact same problem as you! and also the same problem with 3rd gear to 4th changing really late sometimes 2800 or above not sure. Even sometimes speeding up on the freeway to 100km (60mph) it doesnt change from 6th to 7th stays at 2000rpm and then maybe a minute or 2 later it goes to 7th.

I've had 2 seperate MB dealers look at it and both times they just run diagnostics and done a software upgrade and still the same.

mikapen

My problem is slipping or revving while going into 4th gear. I had the above done at 2600 miles - the situation improved but now it's a little worse again (9600 miles).

primatives

i emailed my mb dealer and he said that the 11 model is comparable to other MB m class cars and that there is nothing worng he said they can check for the latest updates from germany and update it and try and smooth out the gear changing and that the issues with the 08/09 they are aware of and has been fixed and if there was anything with the 11 model they would know.

i have the dianostic reports emailed to me and a copy of the email so if anything happens in the future i can have proof.

jkaetz

Seems to be a common "non-problem". The wify's '11 Bluetec exhibits the same behavior on a 3->4 shift. Took it to the dealer twice around 2000 miles and the first time they fixed "faulty shift adaptations" but the problem came back. The second time we were told all was normal. I just drove it today with 8000 miles and the 3->4 shift slipped quite badly during the initial warm up period. It usually never does it after it's warm. It's a bit disappointing for a luxury car when I've had any number of older, and much cheaper, cars that never showed this kind of behavior. I figure there are four years or 50k miles for things to break before I'll worry about it seriously.

MBE350Driver

I have the same issue with 2013 ML350 BlueTec. On first start of the day I get a hard shift from 2-3rd and then a big slip with driveline jolt from 3rd -4th. This should not be accepted at any operating or ambient temperature. Not even above the arctic circle. It doesn't happen in the service loaners or in the lesser vehicles I rent when on vacation. My dealer is working with driveline engineering group and have tried several different software changes along with a different valve body. I still have the problem and MB is still working on it. It will be fixed or they're going to buy it back soon.

djjoonie

My 2010 bluetec does the same thing until the car is warmed up but you can shift earlier with the right side paddle shifter even when u are on 'd'. It wouldnt shift if ur rpm is too low or if you are in uphill but it will let you when its over 2000rpm. Try to upshift when u reach 2200 rpm @ 3rd gear. This way ull atleast know that the tranny isn't slipping. Hope this helps!