# Trouble with smooth shifting - E46 M3



## Xiled1 (Jan 24, 2004)

I've had my M3 for about 3 months now and I am still haveing trouble knocking off smooth shifts in normal driving. If I drive more aggressively, the shifting smooths out. Also if I drive very conservatively(shift around 2000 or so RPM) its smooth. The trouble seems to come when accelerating conservatively to around 3000 RPM and then shifting. 1-2 being the worse and then improving from there. I think you have all heard this before. 

I believe this trouble is due to the delay in the DBW throttle. I'm having problems with the timing. So my question is - Is there anything I can do to remove or at least decrease this delay? Perhaps a factory software upgrade that addresses this issue. Or maybe aftermarket such as Dinan. 

Any help is greatly appreciated. At this point I am considering selling the car due to my frustration with the shifting. I'd hate to do that, but I bought the car purely for motoring enjoyment and thats just not happening. For info, I've been driving stick my entire life, I have removed my CDV, and I have the UUC stage III SSK. 

thanks,
Brian


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## sky (Aug 22, 2003)

Xiled1 said:


> I believe this trouble is due to the delay in the DBW throttle. I'm having problems with the timing. So my question is - Is there anything I can do to remove or at least decrease this delay? Perhaps a factory software upgrade that addresses this issue. Or maybe aftermarket such as Dinan.
> 
> Any help is greatly appreciated. At this point I am considering selling the car due to my frustration with the shifting. I'd hate to do that, but I bought the car purely for motoring enjoyment and thats just not happening. For info, I've been driving stick my entire life, I have removed my CDV, and I have the UUC stage III SSK.
> 
> ...


I know what you mean about the DBW. That very slight delay in throttle
response can be a pain in the arse. What seems to work for me is to keep
my foot on the throttle for a slight fraction of a second after I push the
clutch in (you'll feel the revs go up slightly when the load on the engine
is gone). As soon as the revs go up, lift off the throttle, do your 1-2
shift (or any other shift).


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## sky (Aug 22, 2003)

By the way, if you don't want your M3, I'll be happy to take it.


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## TGray5 (Jan 22, 2002)

Xiled1 said:


> I've had my M3 for about 3 months now and I am still haveing trouble knocking off smooth shifts in normal driving. If I drive more aggressively, the shifting smooths out. Also if I drive very conservatively(shift around 2000 or so RPM) its smooth. The trouble seems to come when accelerating conservatively to around 3000 RPM and then shifting. 1-2 being the worse and then improving from there. I think you have all heard this before.
> 
> I believe this trouble is due to the delay in the DBW throttle. I'm having problems with the timing. So my question is - Is there anything I can do to remove or at least decrease this delay? Perhaps a factory software upgrade that addresses this issue. Or maybe aftermarket such as Dinan.
> 
> ...


shifting at 3k is very low and I can't even imagine what 2k is like. With my SMG, if I shift at those levels, I can't really keep up with the flow of stop and go traffic. No reason to shift at those levels IMO.


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## Xiled1 (Jan 24, 2004)

sky said:


> I know what you mean about the DBW. That very slight delay in throttle
> response can be a pain in the arse. What seems to work for me is to keep
> my foot on the throttle for a slight fraction of a second after I push the
> clutch in (you'll feel the revs go up slightly when the load on the engine
> ...


I have actually tried this before and it does work, but I'm not sure its the correct thing to do. By doing so the revs hang on a little before dropping, in the same way they do when driving agressively. My concern is that this method leads to increased clutch wear.

But thanks for the input, it helps to know that I'm not alone in having difficulties.


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## glaws (Feb 21, 2002)

*EVERYBODY* has had trouble with the 1-2 shift. The Getrag shifter on the E46 M3 is very notchy.


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## Xiled1 (Jan 24, 2004)

glaws said:


> *EVERYBODY* has had trouble with the 1-2 shift. The Getrag shifter on the E46 M3 is very notchy.


Agreed, the shifter IS notchy. But my problem lies in the timing of application of the throttle with release of the clutch. I tend to release the clutch before the RPM's have risen to a matched point - this causes bucking. OR I give too much throttle and the engine revs up before clutch engagement is complete - also causing jerking, but in the opposite direction. Mostly the former though. After installation of the UUC SSK I don't have nearly as much trouble with the notchiness.

Thanks for the input.


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## Rich_Jenkins (Jul 12, 2003)

glaws said:


> *EVERYBODY* has had trouble with the 1-2 shift. The Getrag shifter on the E46 M3 is very notchy.


Mr. Glaws - I've wondered about this - never driven an M3 myself. Is it because of the power the xmission has to convey?


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## glaws (Feb 21, 2002)

wingspan said:


> Mr. Glaws - I've wondered about this - never driven an M3 myself. Is it because of the power the xmission has to convey?


 Partly, I think. The shifter comes right out of the (late) M5 and was designed to handle a V8 with a lot more HP. Otherwise I have heard that Getrag shifters are just notchy by nature.

For Xiled - shifting at 2000 RPM is part of your problem. Do you have SPORT engaged?


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## Ajax (Feb 1, 2002)

shift at 4k


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## 16hr Day (Apr 17, 2004)

my shifts can be a little jerky too. It seems like if you don't have the exact mix of clutch and gas. However, when everything is just right it's like hitting the sweet spot with a baseball bat and you hear that crack and you know it was just perfect! :drive:


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## Xiled1 (Jan 24, 2004)

For Xiled - shifting at 2000 RPM is part of your problem. Do you have SPORT engaged?[/QUOTE]

Shifting at 2K is a rarity, only when stuck in traffic and that actually is smooth. Shifting around 3-3.5K is where it tends to get jerky. As for saying, "just shift higher", my daily driving does not always lend itself to that type of shifting. Usually stuck behind someone and the speed limits are in the 35 - 45 MPH range. The actual rpm I am shifting at is not the deciding factor though. Its more dependent on how fast I got to that RPM. If I am driving more agressively, then the revs will hang on a little after the shift and that way they end up at the correct engagement RPM for the next gear. When accelerating slowly, the revs drop off much faster, thus requiring application of the gas to bring the revs up to the proper engagement point. This is the situation that I am having the most trouble with. I feel that if I could remove or at least reduce the throttle delay, I would be able to better match the revs to the gear.

Oh and I do not have Sport engaged when driving with the A/C on. Seems to shift smoother. With A/C off, I seem to do better with SPORT on.


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## glaws (Feb 21, 2002)

I have never experienced enough throttle delay to effect my shifting like that. The only shift that I consistantly have trouble with is the 1-2 which I attribute mostly to the Getrag being notchy. I am in sport mode 24/7 just because I got used to it early on. I realize that you drive in an urban area (as do most of us) but there is no real reason to poot around in 3rd at 2000 RPM - stay in 2nd and let the revs go to 5-6K. Course your milage will go to hell....


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## jetstream23 (Mar 9, 2004)

Is this a 6 sp problem only or are people finding this with the SMG II? I'd imagine that since the clutch is engaged by the computer on an SMG this problem might not be a prevalent on the SMG. Although it is still a manual transmission so there is no torque converter or automatic rev-matching so it could still be a problem I guess.


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## [email protected] (Mar 15, 2003)

Your experience has nothing to do with your shifting style or the gearbox itself. The problem is the clutch...

The problem with the clutches in the E46 (and E39) is the SAC - Self Adjusting Clutch. This new mechanism built into the clutch pressure plate is supposed to keep your clutch pedal engagement point the same as the clutch wears... but in all reality, it's a case of engineers with too much free time. They have added a layer of complexity and feedback isolation, filling a need that didn't need filling - like anyone ever notices that their clutch engagement point as moved 1/2" over 50K miles?

It's this automatic adjusting that is making your clutch engagement feel weird and not contollable in a smooth manner. Additionally, the SAC mechanism can be affected by temperature. This explains why sometimes you can get off a clean shift, other times you cannot.

The SAC mechanism itself causes other problems; it over- or under-adjusts the pressure plate and therefore causes the clutch to slip or burn out prematurely. They are also known to shift, causing the pressure plate release fingers to slip off the plate, keeping 1/3 of the pressure plate engaged at all times. Bottom line is that the only fix is a complete clutch job, and your dealer is likely to claim "driver abuse". We've seen it happen too many times.

Our custom clutches have the SAC disabled. Clutch feel is normalized, shifting smoothly is no longer dependent on what "mood" the SAC is in.


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## Pinecone (Apr 3, 2002)

Havnig recently driven a manul M3 recently (mine is SMG), I find that the tranny is not notchy. I have to guess that most of you have not had any experience with a tranny designed for high output. Trust me, there are some REALLY notchy trannys out there. 

Second, I found no problem with shifting at any RPM. If it is a timing problem, you should be able to adjust your timing to handle it. Again, maybe lack of experience. Although the car I drove did have the CDV removed.


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## TLudwig (Mar 30, 2004)

sky said:


> I know what you mean about the DBW. That very slight delay in throttle
> response can be a pain in the arse. What seems to work for me is to keep
> my foot on the throttle for a slight fraction of a second after I push the
> clutch in (you'll feel the revs go up slightly when the load on the engine
> ...


I've had this same issue off and on, and this is exactly what I've been doing to compensate. I doubt this would wear out your clutch significantly faster.


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## flashinthepan (Jul 25, 2003)

Pinecone said:


> Havnig recently driven a manul M3 recently (mine is SMG), I find that the tranny is not notchy. I have to guess that most of you have not had any experience with a tranny designed for high output. Trust me, there are some REALLY notchy trannys out there.
> 
> Second, I found no problem with shifting at any RPM. If it is a timing problem, you should be able to adjust your timing to handle it. Again, maybe lack of experience. Although the car I drove did have the CDV removed.


For what its worth, My M3 is equally smooth as my 330 was & I have a very easy to use gearbox ? All factory, no CDV removed. Is it as smooth as a Honda ? not quite, but as pine suggests, for the power its very good ? I have had muscle cars that would make you say the M3 is butter smooth.

Maybe I am a lucky one ??

BTW for strictly trivia purposes, if you want to feel a notchy tranny ? try an old Triumph Spitfire...OMG !!! it was a victory just getting to your destination.


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## Mr. The Edge (Dec 19, 2001)

I have had no problems shifting in my nearly 3 years of ownership


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## armaq (Apr 18, 2003)

If you think the M3 has got a notchy tranny try a manual IS300. It's impossible to shift smoothly in that car


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