Thoughts on why E46 M3 had an SMG but the E39 M5 did not?

[Captain Apex]

So arguably an M5 is more a cruiser than a sporty M3 and an SMG is more a cruiser transmission than a enthusiast manual transmission.

So why did the cruiser get the enthusiast transmission option only and the more likely to be a track car got both options?

Now I know the E39 M5 was made from 1998-2003 and the E46 M3 was made from 2000-2006. They kind of stair step each other. I assume the sole reason was the E46 M3 was a newer car so it got the new SMG transmission while BMW did not waste time to put the new transmission in a car near the end of its run (E39 M5), but I wanted to hear your thoughts?

[Stoo]

Don't forget the E46 had the SMGII.

SMG originally came to the fore in the E36 M3...

[Captain Apex]

Originally Posted by Stoo

Don't forget the E46 had the SMGII.

SMG originally came to the fore in the E36 M3...

I had no idea the E36 had an SMG.

Well the E46 SMG gets alot of hate, how was the E36's?

[smrtypants44]

I would argue the opposite, that the smg is the sportier, track oriented transmission and the 6mt more of a cruiser.

[Housekeeping]

Thank God the E39 didn't get SMG...... total crap, would have destroyed the car.

[BimmerBahn]

Originally Posted by Sy1616

Thank God the E39 didn't get SMG...... total crap, would have destroyed the car.

yup!

[PKL]

I had a 2006 E46 M3 with SMG and I thought it was fun at the time. But I missed my manual and now I will simply never buy a non manual transmission car ever again. I just miss it too much. I live in LA too! Pump that clutch pedal baby!

[feuer]

Originally Posted by Stoo

Don't forget the E46 had the SMGII.
SMG originally came to the fore in the E36 M3...

US never got the S50B32 with 321hp and 6 speed manual either, so is OK if the existence of the SMG prior e46 is unknown

[-BEASTMW-]

Two reasons:
1. The aforementioned two-year gap (think how fast we went from clunky single clutches to awesome dual clutch boxes). I remember reading that SMG simply wasn't ready.
2. I think BMW was not trying to invest a huge amt of money into the E39 M5, which makes it all the more amazing they did such a great job. They had thought the 540i would be enough (this is the true story on record) but when AMG came out with the first E55, BMW unexpectedly had to step it up, and so the E39 M5 was a bit rushed, cutting corners in places. Evidence: Extensively modifying the 540i engine but using the same headers (very restrictive) and same size clutch (definite weak point). They weren't about to sink a ton of money into developing an SMG for the M5 - especially considering it would never sell in the volume of the M3.

[STR8-6IX]

the e39 did not come with an SMG because they did not want to bother building one that could handle the extra power

[captain_slow]

E46 was a newer platform by several years, most likely answer. Initial design work for the e39 would have been done in the early 90s

[lemetier]

Originally Posted by STR8-6IX

the e39 did not come with an SMG because they did not want to bother building one that could handle the extra power

That wasn't the reason

This is attached to an S62...

[STR8-6IX]

Originally Posted by lemetier

That wasn't the reason

This is attached to an S62...

how do you know this SMG was not modified? because i can guarantee you that an SMG built to work with 260 ft/lb of torque cant just be swapped into the e39 m5 making 270 ft/lb just like that without modifying the transmission.

why else do you think BMW did not include the SMG for the e39 m5?

[yousefnjr]

Who knows, just be thankful

E39 prices have been climbing, good ones were ~$30-35k last time I was looking. I've seen 6MT E60's for less!

[mirob]

Hmmm, I liked my SMG II...when it wasn't broken...

[mirob]

Originally Posted by STR8-6IX

how do you know this SMG was not modified? because i can guarantee you that an SMG built to work with 260 ft/lb of torque cant just be swapped into the e39 m5 making 270 ft/lb just like that without modifying the transmission.

why else do you think BMW did not include the SMG for the e39 m5?

I can't speak for that specific example, but SMGs in AA/ESS/G-Power (pick a tuner that supercharged the M3) M3s had to handle A LOT more power/torque than what the S62 was putting out. Not to mention HPF M3s.

I can't speak for reliability with the increased power/torque because mine was stock and had minor issues. I do know that I changed the clutch (as preventative maintenance) at 105K miles and the old clutch was still at a solid 75%.

[lemetier]

Originally Posted by STR8-6IX

how do you know this SMG was not modified? because i can guarantee you that an SMG built to work with 260 ft/lb of torque cant just be swapped into the e39 m5 making 270 ft/lb just like that without modifying the transmission.

why else do you think BMW did not include the SMG for the e39 m5?

The E46 and E39 shared the same Getrag 420g transmission rated for 369ft/lb, though the the latter utilizes a HD clutch disc.

There was almost no consumer desire for SMG on the E39 M5 nor the vehicle I posted earlier...

[STR8-6IX]

Originally Posted by mirob

I can't speak for that specific example, but SMGs in AA/ESS/G-Power (pick a tuner that supercharged the M3) M3s had to handle A LOT more power/torque than what the S62 was putting out. Not to mention HPF M3s.

I can't speak for reliability with the increased power/torque because mine was stock and had minor issues. I do know that I changed the clutch (as preventative maintenance) at 105K miles and the old clutch was still at a solid 75%.

are you talking about the e92 or e46? because the e92 doesnt really have an SMG, its a dual clutch which is much better designed then before and can handle some serious power.

Originally Posted by lemetier

The E46 and E39 shared the same Getrag 420g transmission rated for 369ft/lb, though the the latter utilizes a HD clutch disc.

There was almost no consumer desire for SMG on the E39 M5 nor the vehicle I posted earlier...

I wonder why the SMG was somewhat popular in the e46 then.

[mirob]

Originally Posted by STR8-6IX

are you talking about the e92 or e46? because the e92 doesnt really have an SMG, its a dual clutch which is much better designed then before and can handle some serious power.


I wonder why the SMG was somewhat popular in the e46 then.

I'm talking about the SMG II in the E46 M3, not about the DCT in the later cars.

Even still, the DCT in the F10/12/13/06 Ms can only handle about 650-700 WTQ before the clutches start slipping...ONLY. LOL. DPs and a Stage 2 tune will get you there easily. But I digress...

I really like the SMG in the M3 because it was lightning fast (not as fast as the DCT) but more importantly, because in the fastest setting it would make a very distinct mechanical sound, it was just satisfying to drive. However, it was shit around town, especially in low speeds, and it was impossible to launch effectively off the line...either massive wheel spin or bog.

I'd side with the people that say that this transmission is definitely more suited for the track.

[STR8-6IX]

Originally Posted by mirob

I'm talking about the SMG II in the E46 M3, not about the DCT in the later cars.

Even still, the DCT in the F10/12/13/06 Ms can only handle about 650-700 WTQ before the clutches start slipping...ONLY. LOL. DPs and a Stage 2 tune will get you there easily. But I digress...

I really like the SMG in the M3 because it was lightning fast (not as fast as the DCT) but more importantly, because in the fastest setting it would make a very distinct mechanical sound, it was just satisfying to drive. However, it was shit around town, especially in low speeds, and it was impossible to launch effectively off the line...either massive wheel spin or bog.

I'd side with the people that say that this transmission is definitely more suited for the track.

meh, I would stay away from any sort of SMG. they dont shift smooth and are unreliable, really at the early stages for this type of tech. the newer DCT's are great, but I would still rather get a manual.

[Terraphantm]

Originally Posted by STR8-6IX

how do you know this SMG was not modified? because i can guarantee you that an SMG built to work with 260 ft/lb of torque cant just be swapped into the e39 m5 making 270 ft/lb just like that without modifying the transmission.

why else do you think BMW did not include the SMG for the e39 m5?

It's physically the same transmission as the 6-speed (which asides for the bell housing, is the same between the E46 M3 and E39 M5). Handling the torque isn't the issue. Don't forget there are 1000whp cars using that transmission.

They probably didn't do it because they figured there wasn't a market for it.

[Obioban]

According to BMW's marketing material at the time, "because it's a drivers car, the M5 is available exclusively in SMG". How far things have changed :P

I'd say the real reason is because it's not at all in keeping with the character of the car. The e39 M5 is relaxed, comfortable, easy fast. It also doesn't need to be shifted quickly to get the most out of it because it has power at all RPM. The SMG is not relaxed/comfortable/easy fast-- you have to work to make it smooth. Its benefit is that it makes it easier to keep it in the powerband on track-- the M5 isn't great on track and the powerband is everywhere.

I see no technical limitations on it-- same transmission as the e46 M3 (SMG trans and 6mt trans were the same trans-- just with a human or a hydraulic robot operating it), same ecu as the e46 M3 (talks to the smg ecu).