[AudiA4]

In Comfort mode, I find modulating braking to a consistent feel in normal driving to be unnecessarily difficult due to the transmission "downshifting" as I'm coming to a stop. I get that this would be helpful in spirited driving if I were in Sport mode, but I'm just trying to drive around town and coming to an even stop at a red-light like a normal human being! Anyone else find this annoying? Any way around this?

[HighlandPete]

Originally Posted by AudiA4

In Comfort mode, I find modulating braking to a consistent feel in normal driving to be unnecessarily difficult due to the transmission "downshifting" as I'm coming to a stop. I get that this would be helpful in spirited driving if I were in Sport mode, but I'm just trying to drive around town and coming to an even stop at a red-light like a normal human being! Anyone else find this annoying? Any way around this?

Similar to the issues in this Topic?

https://x3.xbimmers.com/forums/showthread.php?t=1963991

[AudiA4]

Originally Posted by HighlandPete

Similar to the issues in this Topic?

https://x3.xbimmers.com/forums/showthread.php?t=1963991

Nope. That thread is about "touchy" brakes with too much initial bite. I'm talking about the transmission downshifting WHILE I'm braking forcing uneven deceleration. It's super annoying. I want the transmission to stay out of the braking process in Comfort mode.

[HighlandPete]

Originally Posted by AudiA4

Nope. That thread is about "touchy" brakes with too much initial bite. I'm talking about the transmission downshifting WHILE I'm braking forcing uneven deceleration. It's super annoying. I want the transmission to stay out of the braking process in Comfort mode.

Have you read some of the issues in the thread?

[AudiA4]

Originally Posted by HighlandPete

Have you read some of the issues in the thread?

Yes, I see where one person described transmission downshifting as an issue, but that doesn't pertain to the OPs original post about initial bite.

[HighlandPete]

Originally Posted by AudiA4

Yes, I see where one person described transmission downshifting as an issue, but that doesn't pertain to the OPs original post about initial bite.

I have to ask if you have the sharp initial bite? Why I ask, I see part of the issue in the other thread, related to the smooth stops, (it would appear others could have the downshift issue), could well be linked to the initial bite.

A sharp initial bite could be initiating the down changes. Even without a sensitive initial bite, it doesn't seem normal in Comfort mode to trigger aggressive downshifts. Transmission management will be assessing the speed when starting to brake, determine the deceleration rate, or read the braking pressure. Aggressive downshifting indicates quite heavy braking.

[HighlandPete]

BTW, do you have the 48V MHT on your model?

[AudiA4]

Originally Posted by HighlandPete

BTW, do you have the 48V MHT on your model?

Yes

[AudiA4]

Originally Posted by HighlandPete

I have to ask if you have the sharp initial bite? Why I ask, I see part of the issue in the other thread, related to the smooth stops, (it would appear others could have the downshift issue), could well be linked to the initial bite.

A sharp initial bite could be initiating the down changes. Even without a sensitive initial bite, it doesn't seem normal in Comfort mode to trigger aggressive downshifts. Transmission management will be assessing the speed when starting to brake, determine the deceleration rate, or read the braking pressure. Aggressive downshifting indicates quite heavy braking.

No issues with initial bite, just gear downshifts midway through coming to a stop that disrupt smooth deceleration. I'll test aggressive versus passive braking to see if it behaves differently.

[satz]

Interestingly my issue with my transmission when I slow down to come to a stop, is that is often doesn't drop down a gear quickly enough, so if I suddenly need to accelerate, it lags a lot because it's sitting in a too-high gear.
And that's in sport mode!

[HighlandPete]

Originally Posted by AudiA4

No issues with initial bite, just gear downshifts midway through coming to a stop that disrupt smooth deceleration. I'll test aggressive versus passive braking to see if it behaves differently.

Testing the difference is a good idea. See if it is due to driver influenced adaptations. Keep in mind the way you lift the throttle and apply the brakes will be compared against the thresholds in the control unit. One statement used is: "The demand for higher dynamics is detected on the basis of these values".

If your actions call for "higher dynamics", you'll get them.

[HighlandPete]

Originally Posted by satz

Interestingly my issue with my transmission when I slow down to come to a stop, is that is often doesn't drop down a gear quickly enough, so if I suddenly need to accelerate, it lags a lot because it's sitting in a too-high gear.
And that's in sport mode!

Similar to the comments in my post above, your actions, how you are slowing down could be influencing the gear selection. The fact you are in Sport mode, with different thresholds than Comfort mode, could mean at times you are giving inputs that do not demand any engine braking. For example, you may not be aggressive enough (throttle/brake actions) to 'request' higher dynamics.

[Gritty]

Originally Posted by AudiA4

Nope. That thread is about "touchy" brakes with too much initial bite. I'm talking about the transmission downshifting WHILE I'm braking forcing uneven deceleration. It's super annoying. I want the transmission to stay out of the braking process in Comfort mode.

Agreed annoying, although I posted about "touchy" brakes soon after getting the car. I think a big part of it was actually the downshifting while braking.

[rob175]

With almost 30,000 miles on my 2020 X3 30i the "feel" of my brakes while the engine downshifts in "comfort" mode, seems pretty normal to me. It acts just like any brake/traditional transmission I've ever driven.

[botan22]

hello
I also feel uneven breaking both in comfort and eco pro (to be honest have not driven much in sport to observe this). I don't feel any downshifting. Just shudder when doing light to medium breaking. and it can continue for as long as I'm breaking - there would not be that many shifts in the transmission
no feeling of a specific side/wheel doing that pulsing (i.e. car is not going left or right). and it's not as abrupt as ABS kicking in.
this card does not have the hybrid option, but it has the 'smart' generator that charges conventional batteries during breaking, so my only theory is that it may be creating some pulsing by enabling/disabling that regeneration, but I would not expect it to be that strong.
the car (X3 xDrive 30 2022) is still in warranty so I'll be addressing this with the dealership soon. Just wanted to get a feeling as to how unique my problem is.

[nbrewno]

Originally Posted by botan22

hello
I also feel uneven breaking both in comfort and eco pro (to be honest have not driven much in sport to observe this). I don't feel any downshifting. Just shudder when doing light to medium breaking. and it can continue for as long as I'm breaking - there would not be that many shifts in the transmission
no feeling of a specific side/wheel doing that pulsing (i.e. car is not going left or right). and it's not as abrupt as ABS kicking in.
this card does not have the hybrid option, but it has the 'smart' generator that charges conventional batteries during breaking, so my only theory is that it may be creating some pulsing by enabling/disabling that regeneration, but I would not expect it to be that strong.
the car (X3 xDrive 30 2022) is still in warranty so I'll be addressing this with the dealership soon. Just wanted to get a feeling as to how unique my problem is.

Sounds to me like you might have warped rotors. If you feel it in the seat it is usually rear rotors, if you feel it in the steering wheel it is usually front rotors.

[br438]

The transmission downshift in the 48v m40i can be super annoying.

Might it be compounded by a "rev-matching" feature?


The most annoying behavior (to me) is when it is engine braking, the lets off the engine brake, and downshifts to more aggressive engine braking. It sucks pretty bad for anyone not in the driver's seat and does mess with your perceived/planned stopping distance in everyday driving.

[sorocknroll]

I have the same problem. The 3-2 downshift has a lot of engine braking that slows the car rapidly and unevenly. I find that other shifts are noticeable, I wish they were smoother, but the 3-2 is really uncomfortable. This happens at roughly 20 kph/12 mph.

I've searched a lot on the forums and some people have this problem, others don't for whatever reason. I took it to the dealer 3 times, and they've updated the software and reset the transmission adaptations. The software update helped a bit, but did not eliminate the problem.

Mine is a 2019 M40i without the mild hybrid system.

I'm going to order xHP. I contacted their support and they think it will be able to resolve the problem by changing the shift point.

[vrships]

The 2nd time I drove this car I immediately noticed this brake jerk effect during downshifts.

For me it's a very obvious thing and it's haunted me for 3 years and not too much I can do about it (maybe eco pro mode is better than comfort, slightly?).

I couldn't quite understand why this has not been complained about for majority of the users. It's almost the only car that has such jerkiness during braking of all auto-tranny car I've driven and I feel anyone will be comfortable about it.

But then I realize probably it is just an issue for *some* G01/02? Maybe most of these series don't really have this issue at all and they simply don't know about it. And for some unlucky users who has this in their car since the 1st ride, we thought this is normal and intended? Maybe it's a batch of faulty tranny of tune that haven't been acknowledged by BMW at all?

[glennbk]

I think this has been an issue for some time. Experienced it in a 2013 X3 35i I almost bought. I would come up on a light to stop and the light would change. I apply the gas and it would shift down to 1st. It was like a bucking bronco. Threw you back in the seat.

[HighlandPete]

Originally Posted by glennbk

I think this has been an issue for some time. Experienced it in a 2013 X3 35i I almost bought. I would come up on a light to stop and the light would change. I apply the gas and it would shift down to 1st. It was like a bucking bronco. Threw you back in the seat.

Nothing new in some users having transmission lurch or jolt. This also goes back to the 6HP gearbox. BMW and Jaguar had TSBs for the issues as far back as 2008.

I believe this topic for the G01, has several issues involved and being discussed. Brake modulation, gearbox characteristics associated with braking, inducing engine braking, and driver influenced adaptations. Not easy to fully understand where a particular fault lay.

[AllBlackBimmer]

I did originally notice it, but now i only really notice it at certain speeds - seems very creeping up to say a stop sign, its more noticeable than say, getting off a highway ramp.
I dont really find it annoying though... i also drive a 6spd manual so I am used to have a transmission/engine act a certain way.

Should it have as aggressive engine braking as it should?
Who knows - but people buy "sporty" cars and then immediately complain about "harsh ride" and "aggressive engine braking"...

The reason is... #BecauseRaceCar
But in all seriousness, you can't have your cake and eat it too.
People talk on this forum like the X3 m40i is a "race car" so don't be surprised when it does "race car" things