[IoT]

Anyone know for sure about the "SMG" transmission in the E90 - is it gonna be true SMG like in the e46 M3 or some sorta variation of it? Thanks.

[vivid]

I believe that it will be the SMG III which is used in the new M5 & M6, the E46 M3 used SMG II... SMG I was only availble on the E36 M3 in Europe but had so many problems that it never made it to the US

[Jason]

This is from the BMW press release on the E90:

6-speed Sequential Manual Gearbox

Available on the 330i as of September ’05 production, this is an electrohydraulically shifted, electronically controlled rendition of a 6-speed manual transmission, including an automatic clutch – a wholly different transmission from the STEPTRONIC automatic. There is no clutch pedal; the driver selects the desired mode (N, R, D, S) with a consolemounted selector lever, and can execute manual shifts via that lever or two “paddles” on the steering wheel. SMG fully preserves the performance of a manual transmission, entails little or no penalty in fuel economy, and facilitates both automated and very sporty driving.

Features and characteristics of the SMG driver interface includes the following:
• A Drive mode (D) in which shifting is automated
• A Sequential mode (S) in which shifting is mostly driver-controlled
• A Sport button on the console, which selects the SMG Sport program
• An instrument-panel display of the gear currently engaged.

In D, shifts are automatic, programmed according to how the driver is currently driving; more aggressive driving effects shifts at higher speeds. D is not a substitute for the D of a fully automatic transmission, but rather a convenient operational mode for those times when the driver values ease of driving over maximum performance.

With S selected, the driver essentially controls all shifting by means of the shift lever or paddles –
• Tip lever or paddle(s) rearward = upshift
• Tip lever or paddle(s) forward = downshift
– with the following exceptions:
• If the driver takes the engine up to its rpm limit, SMG will automatically shift to the next higher gear.
• Upon deceleration, as the engine comes down to approximately 1100 rpm, SMG selects the next lower gear. When the vehicle comes to a stop, SMG selects 1st gear automatically; upon moving off, the driver again chooses each upshift.

Engaging the Sport program via a console button influences shifting as follows:
• In S, shifts occur more quickly (sharply).
• In D, shifts occur not only more quickly, but at higher road speeds. This is parallel to the Sport mode of BMW automatic transmissions.

An Acceleration Assistant function (also referred to as Launch Control) is available for very sporty driving: With Sport activated, the driver presses and holds the DSC button (on the dash) for 3 sec. or more, then presses the accelerator to the floor. The engine is automatically revved to the optimum rpm for a wheel-spinning start and the vehicle is “launched.” The Owner’s Manual cautions: “Do not use the Acceleration Assistant too frequently, as this could cause premature wear of the components.”

With all transmissions, a new generation of differential is employed in the 3 Series. Its main distinction is a new type of bearing, called “double angular-contact ball bearing.” These bearings reduce oil temperatures within the differential, with benefits for both function and durability. Power losses due to oil flow are reduced and gear design has been adapted to the new bearings, with the overall results that efficiency is increased (meaning a small increase in fuel economy) and durability is enhanced.

[YYdoodle]

Originally Posted by vivid

I believe that it will be the SMG III which is used in the new M5 & M6, the E46 M3 used SMG II... SMG I was only availble on the E36 M3 in Europe but had so many problems that it never made it to the US

vivid, any idea what the difference between the SMGII and III is?

[Tech@BMWSF]

No the transmissions are made by two differant companys. ZF & Getrag.

[LOLrance]

wow, this thread got bumped from more then 2 years ago.

[mkoesel]

Originally Posted by l4wr3nc3

wow, this thread got bumped from more then 2 years ago.

Yep, and the SMG option for the E90 never did end up materializing.

[Crazy Bimmer]

They offered SMG I for the E46 for a year or two I think. Maybe they saw that many people werent buying them so they trashed the idea for the E90.

Sucks too since I would have gotten it.

[e92man]

on the e90, unlike the e46 m3 and m5/m6 there is no selector for shift aggresiveness. in other words, on the m models u can chose how sporty u want the shifts to be. on the normal cars its just 2 ways to shift. auto and manual. at least thats how it is in the U.S.

[e92man]

Originally Posted by Terps

vivid, any idea what the difference between the SMGII and III is?

my post before this tells the difference

[LOLrance]

Originally Posted by e92man

on the e90, unlike the e46 m3 and m5/m6 there is no selector for shift aggresiveness. in other words, on the m models u can chose how sporty u want the shifts to be. on the normal cars its just 2 ways to shift. auto and manual. at least thats how it is in the U.S.

The e90 is NOT SMG. It is a auto with a torque converter. You cannot choose shift aggressiveness because it is not an SMG.

As far as the whole "SMGII VS SMG III". SMGII is used in the e46 m3. From personal experience, the SMGII is has very harsh and jerky shifts. It is uncomfortable for everyday driving (yes even when on S2 and S3). SMGIII was introduced and put in on the m5's and m6's. The m5's SMGIII is incredibly smooth and feels like a totally different trasmission then SMGII.