[Roy46]

Hi everybody!

I have a problem with the SMG transmission; if I'm standing in front of a traffic light for a minute or more, without my foot on the brake. I push the throttle when the traffic light turns green, I get a really big bang in the transmission. It is really that hard that you will think the transmission will fall under the car. If I push the brake all the time in front of the traffic light, I don't have this problem. The display shows the car is in the 1st gear, but it feels like it is between the 1st and the 2nd gear or between Neutral and the 1st gear, until I push the throttle, then it goes in the 1st with the big bang.

I brougth the car to my local dealer (in The Netherlands) and they could'nt find anything. The only thing they say is that they can try to replace the clutch which will cost me around EUR 1.300,- because the car is 2.5 years old now. I don't want to pay anything because this is really not right and I think there is a problem in the SMG.

Do some of you experienced the same?

 

[Andrey]

I know what you're talking about. Happens sometimes to me as well, and sometimes I experience the same when coming to a stop. When the wheels almost stop running i hear a bang.
I wish we had some decent dealers in the Netherlands. Everytime I bring my car in I already know they won't find anything. All they do is hook it up to the computer where there are 0 messages and that's it then.

 

[taheemr]

I too had this problem on my old and new m6, had the clutch and flywheel changed, seems to have fixed the problem, it stil happens from time to time but no where near as harsh as before.

At times it was like someone had shunted the car from the rear.

If your cars only 2.5 yrs old, whats the problem with getting this work done under warranty

 

[JonnybravoM3]

From my experience the sound is normal but if it happens all the time it may be best to ask the dealer to drop the transmission and take a look at it and see if the clutch needs replacing. I don't understand why they would want to charge you in that case as it should be covered by warranty (3 yrs)?? I just had my clutch replaced along with some other parts and it was all covered under warranty and I bought my car in Jan '09 so my warranty is still valid until Jan '12 so I didn't pay a penny.

 

[whatheheck]

To my limited knowledge -hearing a BANG sound on the SMG is NOT normal.

I never experience any bang sound on my 2006 M6.

If your car is still under warranty - take it to the dealership.
If they come back and said they cant find anthing wrong - take them out for a drive with you and show them.

And if the bang sound continues to happen and your beast is still under warranty - take it back to the dealer and park it there and ask for a loaner.,
Tell them to fix it and call you once the issue is resolved. That's what warranty is for.

If your car is no longer under warranty - then sorry, no choice but to pay the dealer to fix your car.
And as we all know - BMW's are expensive cars to own and maintain.

 

[autodoc]

I believe that after standing still with engine running and foot of brake,smg logic is to shift into neutral,when you keep your foot on the brake the car will stay in gear. You are feeling car shift hard into gear......Keep your foot on brake when stopped....if it happens again try putting shifter into neutral then back into first and you shouldn't feel clunk. I believe there is a tsb from bmw about condition. I will look into it tomorrow at work.

 

[David Ajax III]

Hi everybody!

I have a problem with the SMG transmission; if I'm standing in front of a traffic light for a minute or more, without my foot on the brake. I push the throttle when the traffic light turns green, I get a really big bang in the transmission. It is really that hard that you will think the transmission will fall under the car.

When this occurs, are you driving in S Mode or D Mode?

 

[Tony1K]

Same thing happend to an 06 M5 I had... Dealer changed the Clutch and Flywheel and it was good.

 

[Roy46]

Thanks for your answers guys. I always drive in the S mode, so I actually don't know if it also occurs in the D mode.
By the way Andrey, do you live in Holland as well? I think I'm taking the car to a German dealer as we are not far from the German border.

 

[gkinvest]

Gentlemen,

What I am about to tell you is so certain as is ny name. Verified and crosschecked with the most experienced mechanics.

A SLIGHT noise occasionally is into acceptable SMG limits. When BANGS start ( like you are rear ended ) it is only ONE THING.

The hydraulic SMG pump. 3500 $ plus labor. End of story.

Regards,

George

 

[whatheheck]

Yikes!

Aint cheap!

Thanks for the great info George.

Gentlemen,

What I am about to tell you is so certain as is ny name. Verified and crosschecked with the most experienced mechanics.

A SLIGHT noise occasionally is into acceptable SMG limits. When BANGS start ( like you are rear ended ) it is only ONE THING.

The hydraulic SMG pump. 3500 $ plus labor. End of story.

Regards,

George

 

[David Ajax III]

Gentlemen,

What I am about to tell you is so certain as is ny name. Verified and crosschecked with the most experienced mechanics.

A SLIGHT noise occasionally is into acceptable SMG limits. When BANGS start ( like you are rear ended ) it is only ONE THING.

The hydraulic SMG pump. 3500 $ plus labor. End of story.

Regards,

George

George, mine banged loud the first day or two, but I attributed it to lack of experience in shifting (not making sure to downshift manually to first after a near stop, or short stop at a light that changed before a full stop). But I do get quite a bang shifting from first to second at the redline IF I LIFT UP ON THE THROTTLE A BIT, but not so much if I leave the pedal to the firewall and let the computer handle the throttle. Should I have it checked?

 

[V10PWR]

I had an e46 M3, and i was hearing many noises from the transmission. My local BMW dealer told me that SMG's do make noise! I had the car for two more years , and i could still hear the noise every once in a while some days more than the other days, but other than noise no problem. I mean ZERO problems. Didn't even touch the transmission. I am very confident in the dealer I'm taking my car to. I have been going to this dealer for several years on many BMWs I have owned, and they have never been wrong on their diagnose.
I have to tell you though, the SMG drive logic might have a play in such behavior.

 

[q8kamikaze]

same here i heard this bang before maybe 2 - 3 times , i think it sounds normal cause the dealers checked my transmission
and nothing wrong

 

[Roy46]

Thanks for your answer George! I owned a standard E46 M3 and a M3 CSL for 5 years and their SMG bangs into the gears, but that's normal. But in those years I have never heard those kind of bangs I experience with the M6. Anyway the SMG in the M3 E46 and especially the CSL are way quicker than in the M6. I will bring the car to a German dealer because they have more experience
with the M cars than the dealers in Holland.

 

[Andrey]

Yep, I am from the Netherlands as well. Visiting a German dealer might be a good idea. Those M-only dealers in Germany should have the experience we're looking for. I wonder if any of them are close to the border.

 

[gkinvest]

George, mine banged loud the first day or two, but I attributed it to lack of experience in shifting (not making sure to downshift manually to first after a near stop, or short stop at a light that changed before a full stop). But I do get quite a bang shifting from first to second at the redline IF I LIFT UP ON THE THROTTLE A BIT, but not so much if I leave the pedal to the firewall and let the computer handle the throttle. Should I have it checked?

David, my friend,

What you are saying is totally different than what the OP says. Not trying to play it smart... here but there should be NO NOISES when

shifting ( up or down ) at high revs. That is what the SMG transmission was designed for. The higher the revs the smoother the shifting.

I have never-ever experienced ANY KIND of noise shifting at high revs.

Low revs ... well that is a different story, espesially when you are coming to a stop. THAT is what most people complain about. The

moment that the clutch tries to disengage the motor from the transmission and you get a feeling like something is stuck and abruptly

disengages giving this BANG ( like you are rear ended ). This is normal if it happens randomly AND the noise is a pure mechanical low-pitched

sound ( low volume, small bang not BIG BANG ). Gosh can you replicate sounds with words ?????

From a technical point of view as explained to me by my mechanics :

" The hydroelectricmechanic SMG pump is designed to keep the system at high pressure, when in gear, UNDER ALL CONDITIONS. When the

computer tells the pump to let go because a shift is happening or the car is going to neutral, then at that critical moment, if the pump does

not follow exacly what the computer is saying that akward BANG appears. It is normal to get it now and then since the whole system is

perfect for a racing car that is near the red line all the time, but not perfect at all when cruising around at low speeds ( and revs ).

It is lke the car gets confused. And how could it not be ??? Is it ever possible for a hydro-electrical component to follow the exact orders

of a computer-software without some kind of malfunction occasionally ??? "

To my humble understanding people most of you are feared by something that is normal. Other than that when the noise is continous and

high level, check the pump for possible loss of hydraulic pressure.

Hope this long post helps.

Regards,

George

 

[ritchy-69]

Hey guys,
I do not know where you live in the Netherlands, but when it is in the south, go to Kohl in Aachen (near Heerlen)
Kohl is also the owner of Ac Schnitzer, so many experiance workers over there.
I have been there already several times when I had real problems with my E46 M3.
(price level is better then in Netherlands and Experiance is much higher)
Lucky I did not yet had experiance for M6 at Kohl (as i owned my M6 now for only 3 weeks !!)

Greetz
Ritchy

 

[Andrey]

Hey guys,
I do not know where you live in the Netherlands, but when it is in the south, go to Kohl in Aachen (near Heerlen)
Kohl is also the owner of Ac Schnitzer, so many experiance workers over there.
I have been there already several times when I had real problems with my E46 M3.
(price level is better then in Netherlands and Experiance is much higher)
Lucky I did not yet had experiance for M6 at Kohl (as i owned my M6 now for only 3 weeks !!)

Greetz
Ritchy

Thanks for that! I will definitely give them a try. My car is still under the 2-year warrantee and I can take my car
to any BMW dealer in Europe, so no worries there

I hope you're enjoying the M6!

 

[Roy46]

Hi Ritchy, congratulations with your M6, I saw you went from a E46 M3 to a M6, how do you like it. I went from a M3 CSL to the M6 convertible half a year ago, very big difference of course. Aachen is a bit far from me to go for service, as I am close to Kleve.