For New Owners - What I wish I knew when I first bought my E9X M3:

[718GT4]

Thanks for the thread

[dhakop30]

Hello, I called the BMW dealer today, and they informed me that the dealer does not recommend a transmission fluid change for the vehicle's life. I have a 2011 M3, and the transmission is jolting in traffic. Any recommendations?

[DRLane]

Originally Posted by dhakop30

Hello, I called the BMW dealer today, and they informed me that the dealer does not recommend a transmission fluid change for the vehicle's life. I have a 2011 M3, and the transmission is jolting in traffic. Any recommendations?

Respond. “Oh that’s nice. I’d like to schedule a transmission fluid change”.

[Assimilator1]

What he said.

Originally Posted by dhakop30

Hello, I called the BMW dealer today, and they informed me that the dealer does not recommend a transmission fluid change for the vehicle's life. I have a 2011 M3, and the transmission is jolting in traffic. Any recommendations?

Oils (even in gearboxes) get a build up of contaminants over time and are 'worn' down (slowly breakdown) over time, so they do need changing sooner or later.
Up to the e36s they used to recommend oil changes every 60k (something I carried over to my e46s and e90s).
I believe post e90s they re-introduced trans oil changes, albeit at 100k miles. Hmm, now I'm a BMW tech myself I can find out if that's right! lol [edit] Haven't yet found any evidence of 100k trans oil changes by BMW! Only seen mention of lifetime oils

If the DCTs sump pan gasket hasn't been changed already, it'll probably need it by now anyway. I can't remember if they have a filter, but assuming they do, change that too.

[spammysammich]

Pressure filter, suction filter, and a suction jet pump all should be periodically changed as deansbimmer has pointed out in a different thread. I wouldn’t trust any SA that told me otherwise. Especially for a car with over 100k miles on the odo

[Assimilator1]

Gotta link to that thread?

[spammysammich]

Originally Posted by Assimilator1

Gotta link to that thread?

https://www.m3post.com/forums/showthread.php?t=1974649

[BGBF18]

Get a battery tender.

Efficient dynamics. Aka, the alternator has a clutch and decouples to reduce engine drag when not needed.

So the battery runs the car most of the time and the alt. reconnects when the battery charge is low.

Make sure a used M3 has the correct battery type. Mine did not and it eventually killed the alternator over time. It basicaly ran the alt. to death.

New alt. was $1600 installed + battery.

[Assimilator1]

Originally Posted by BGBF18

Get a battery tender.

Efficient dynamics. Aka, the alternator has a clutch and decouples to reduce engine drag when not needed.

So the battery runs the car most of the time and the alt. reconnects when the battery charge is low.

Make sure a used M3 has the correct battery type. Mine did not and it eventually killed the alternator over time. It basically ran the alt. to death.

New alt. was $1600 installed + battery.

AFAIK the alternator does not have a clutch on our e9x M3s (I know many diesels have a one way clutch in the pulley, but that's for other reasons), the reduced or nil output (when the battery charge is good enough) of the alternator on our M3s is achieved by switching off some or all of the windings in the alternator, again AFAIK.

Where did you read that it has a clutch?

[BGBF18]

Sorry, not a clutch, a de-coupler pulley.

I’ll have to find it. It came from an M3 technical document designed for SAs and technicians.

Also had a discussion w/ the M-certified texhnician who fixed my E90 about this very subject.

[Assimilator1]

Ok, interesting, but I didn't think it had any sort of mechanical decoupling device, but I could stand to be corrected .

Or I could just look it up on BMW's AIR tomorrow morning (I started working their just last month).

[BGBF18]

Oh, cool.

Yeah, I’d love to know for sure - I may have dreamt it.

[Assimilator1]

Originally Posted by BGBF18

Oh, cool.

Yeah, I’d love to know for sure - I may have dreamt it.

I just need to remember to bring my M3s VIN with me, and remember to do it! lol

[DrFerry]

Eyes wide shut.. How much does it cost to fix up a neglected E92 M3 that was purchased for ‘only’ $11K? And what type of repairs does it need?
.

[Assimilator1]

Yep, no such thing as a bargain car!

Originally Posted by BGBF18

Sorry, not a clutch, a de-coupler pulley.

I’ll have to find it. It came from an M3 technical document designed for SAs and technicians.

Also had a discussion w/ the M-certified technician who fixed my E90 about this very subject.

Hmm, well the info I found is a little ambiguous, although what I've found so far points to electrical switching of the alternator (especially pic 2), also I found nothing about a clutch for it. Nor have I ever seen one for any type of alternator (many diesels have a one way pulley, which I suppose you could call a clutch, but it is mechanical only and so not switchable). Pic 1, pic 2
If someone knows where I can find more precise info, then by all means LMK!

[Onodon]

Originally Posted by dhakop30

Hello, I called the BMW dealer today, and they informed me that the dealer does not recommend a transmission fluid change for the vehicle's life. I have a 2011 M3, and the transmission is jolting in traffic. Any recommendations?

I did the complete flush with the pan at 63 k. The high pressure filter was black. Do not listen to anyone that uses the words “lifetime fill” and your car in the same sentence.

[BGBF18]

Originally Posted by Assimilator1

Yep, no such thing as a bargain car!



Hmm, well the info I found is a little ambiguous, although what I've found so far points to electrical switching (especially pic 2) of the alternator, also I found nothing about a clutch for it. Now have I ever seen one for any type of alternator (many diesels have a one way pulley, which I suppose you could call a clutch, but it is mechanical only and so not switchable). Pic 1, pic 2
If someone knows where I can find more precise info, then by all means LMK!

Cool, thanks for looking that up. Would be awesome to know for sure.

[Assimilator1]

Yea would be good to know for 100% sure, but as far as I'm concerned it's 99.5% certain they are electrically switched. Never seen an electro-mechanical clutch on an alternator on a car in the 28 yrs I've been a car tech (they are widespread on AC compressors though).

Also when I changed the belts and pulleys on my M3, I'm fairly sure I looked closely at the alternator pulley for this very discussion back then, and IIRC it was just a plain simple, solid pulley.
I believe the idea of an alt. clutch comes from the mis-reading of turning the alt on/off, some people assume it's done mechanically.
However if someone has solid proof to support that, I'm all ears..... err eyes!

[Assimilator1]

Originally Posted by BGBF18

Cool, thanks for looking that up. Would be awesome to know for sure.

I've been made aware of other sources of info by BMW from a master/senior tech at the dealer I work at.
Turns out that BMW's S-Gate (which I did know of) has a Wikipedia like section called Technipedia (which I didn't know of), within this (amongst much other info! It's very interesting for a BMW geek like me! ) is a section for the Alternator in Drivetrain>Engine electrical system>Alternator>Intelligent Generator Control (IGR).
It starts by saying this was introduced 'Since about 2004', and 'In marketing, IGR is often also designated as "brake energy regeneration".' (which is the term we know for our M3s).
In this it describes switching off the alternator to save fuel and allow more of the engine's power to go to the wheels (when the battery has enough charge).

If the battery is at a high state of charge the alternator only charges on the over run/braking (something I've only ever seen on my long trip to the Nurburgring (I'm in SE England). I have a meter on the dash displaying volts, as well as ECT. When cruising/accelerating it was showing battery voltage of 12.3-12.6v ish, AFAIR).

If the battery charge is middling it'll only provide enough power for electrical consumers when cruising/accelerating and won't charge the battery (quite how it would stop any charge going to the battery it doesn't say, and personally I would make an educated guess that it doesn't. But that the charge rate is minimal. Voltages I see at this level are about 13-14v, ish ).
On the over run/braking it still charges at full capacity.

If the battery charge is low enough* the alternator will charge full time at full capacity, just like old fashioned charging systems. (I typically see in between 14-15v here).

*Annoyingly the techipedia doesn't say at what thresholds these different charging strategies are deployed!

Their is no mention of an alternator clutch, it talks about switching on/off the alternator (an ambiguous term), but more clearly it also mentions activating or energising the alternator, which to me is a clear reference to electrically switching it on.

[DrFerry]

Originally Posted by Assimilator1

I've been made aware of other sources of info by BMW from a master/senior tech at the dealer I work at.
Turns out that BMW's S-Gate (which I did know of) has a Wikipedia like section called Technipedia (which I didn't know of), within this (amongst much other info! It's very interesting for a BMW geek like me! ) is a section for the Alternator in Drivetrain>Engine electrical system>Alternator>Intelligent Generator Control (IGR).
It starts by saying this was introduced 'Since about 2004', and 'In marketing, IGR is often also designated as "brake energy regeneration".' (which is the term we know for our M3s).
In this it describes switching off the alternator to save fuel and allow more of the engine's power to go to the wheels (when the battery has enough charge).

If the battery is at a high state of charge the alternator only charges on the over run/braking (something I've only ever seen on my long trip to the Nurburgring (I'm in SE England). I have a meter on the dash displaying volts, as well as ECT. When cruising/accelerating it was showing battery voltage of 12.3-12.6v ish, AFAIR).

If the battery charge is middling it'll only provide enough power for electrical consumers when cruising/accelerating and won't charge the battery (quite how it would stop any charge going to the battery it doesn't say, and personally I would make an educated guess that it doesn't. But that the charge rate is minimal. Voltages I see at this level are about 13-14v, ish ).
On the over run/braking it still charges at full capacity.

If the battery charge is low enough* the alternator will charge full time at full capacity, just like old fashioned charging systems. (I typically see in between 14-15v here).

*Annoyingly the techipedia doesn't say at what thresholds these different charging strategies are deployed!

Their is no mention of an alternator clutch, it talks about switching on/off the alternator (an ambiguous term), but more clearly it also mentions activating or energising the alternator, which to me is a clear reference to electrically switching it on.

True to BMW form, it all seems very complicated indeed. See pages 8 to 11 of the electrical power management manual attached (for the E9X series [cars as well as others shown on p7]). In fact, see the entire book to understand how BMW's are now rolling cyborgs.. When I search the manual by key word "alternator" it comes up 39 times.. See .pdf file attached.
.
Power Management Manual attached

[Gotfuel]

Just read through this entire thread. Maybe something that would be helpful is for the folks looking at an 08, what are the differences to look for. I’ve read the clutch and flywheel and that it would be upgraded to the newer >=09 spec. No I drive. Older taillights. Generally speaking, if you buy a car without NAV (single hump) what are you giving up? Do you lose access to driver adjustments that can be made? Or do you just have to get used to making changes via an ODBII tuner? Lots of folks with 08’s so I’m less concerned about buying an 08 if I found the right one, but always good to go in to a purchase armed with as much info as possible. I read the 09-13 sticky, but was less helpful, and the 08 was oddly missing from the list.

[spammysammich]

08 has I-drive available. Just the far less desirable CCC version.