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Our future: swap SMG for 6-speed manual?

254K views 504 replies 103 participants last post by  jbash87 
#1 ·
So let's say you want to keep your amazing M5 for a long time ... like 10 or more years. At some time you will be long out of warranty and may face a SMG transmission failure. At that point do you think you might consider swapping out the SMG for a 6-speed manual? Considering that parts for the 6-speed cost something like $4,500 versus $8,900 for the SMG?

I enjoy reading about the classic BMWs from 20 to 25 years ago such as the E24 6 series and the E28 5 series ... and to keep those machines on the road they are always swapping out for parts from other BMWs, especially converting from automatic transmissions to manuals.

So I started to wonder ... what steps are we going to need to take to keep these beasts on the road long-term? Your thoughts?
 
#50 ·
Hasan

Sorry for the really late reply

the photos are not step by step cause too excited to be finished so i only have 7 photos

Hope this will give you some ideas
 

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#55 · (Edited)
Don't forget you will need the corresponding MT flywheel, and you will need to add wiring/provisions for the trans fluid quality/temp sensors, and clutch switch which the DME will be looking for with the 6MT DME flash. I'd upgrade to the 2009/10 diff as well while you're at it. It's a good security at ~300$ or so.

Some other obvious, already mentioned items:

Pedals
Slave
Associated tubing for hydraulics
master reservior cut for fluid drop down to slave
instrument cluster software/coding
trans
clutch
driveshaft (Length difference)
CSB
necessary console trim/boots
Shift linkage (Might as well weight the rod while youre in there.)




DME SW:

7842647: Non US cars with bad fuel quality and a lower service interval on oil changes.
7842502: US SMG and Korean Cars. *
7842641: Non US cars with bad fuel quality.
7842645: Non US cars with some kind of CEL parameter change**
7842795: Japan's version.
7842643: Non US cars with bad fuel quality and a CEL Parameter change(see 7842645 but with bad fuel).
7842649: Non US cars with bad fuel quality and a CEL Parameter change(see 7842645 but with bad fuel) and the lower service interval.
7842639: Non US cars standard tune CO2***
7842504: US Non SMG cars
7842799: Targets The New Euro CO2 standards. This requires a new code file flash as well.



Thanks to M5B user "Ferris" who seems to have access to BMW's SWL system, or did at one time. ;)
 
#58 ·
I love to see the smg guys talk about how fast the smg is next to the 6sp. How's this anyone near or from NY with a smg that wants to test that fact? I have a stock car except for the exhaust so you take off all your crap and we'll race deal ?

I believe it's driver not smg vs stick.:eek
Anyone who wants to play pm me. I'll set it all up, and I will make sure it's all on video.
 
#60 ·
I love to see the smg guys talk about how fast the smg is next to the 6sp. How's this anyone near or from NY with a smg that wants to test that fact? I have a stock car except for the exhaust so you take off all your crap and we'll race deal ?



I believe it's driver not smg vs stick.:eek

Anyone who wants to play pm me. I'll set it all up, and I will make sure it's all on video.


This entire thread was about converting an SMG car to 6MT from a technical perspective for people tired of dealing with SMG problems. I'm not sure where your comment was aimed.
 
#68 · (Edited)


I have begun ordering parts to finally go through with this on my 2007. This is my personal list I have compiled based on new parts, just to get an idea of all the parts related to option 2MA. Don't let the prices listed turn you off to this project; this is a worst case scenario cost situation above. I found a LOT of the stuff used and will only be using new parts where it matters. My final cost for parts alone is just under $2,800 including the trans, new flywheel, clutch kit, pedal assy, and driveshaft.

In addition to parts, the DME will need flashed to the manual software and there are 4 pinning changes that need to be made for the reverse switch, neutral position sensor, yaw rate sensor, and the fluid sensors on the 6MT. Pins need to be moved from the SMG ECU to the DME as the SMG ECU will no longer be there. I'll post details as I get into the conversion after the holiday.
 
#73 · (Edited)
Not at all

I personally have access to 30+ of them so the transmission is not the issue.


We begin the madness with the first major electrical change that needs to happen - adding in the clutch switch. The 6MT cars have a clutch switch/position sensor on the side of the clutch master cylinder on the clutch pedal. If you buy a used clutch pedal assembly, it will probably already be on it, and your job will be a little easier. Here it is:



-




Along with the clutch switch, you will need a 4 pin connector like this:





You then need to run 4 wires after adding the clutch switch, and pinning them into your connector above. Here are the 4 clutch switch wires:



Pin/wire in cavity #1 on the clutch switch needs to be run to chassis ground somewhere. Either tap into a ground comb somewhere close by or terminate a ring terminal onto the wire and ground it manually somewhere. Make sure you verify low continuity to ground over the wire to verify a good connection to ground or the switch won't work and you will have errors.

Pin/wire in cavity #2 on the clutch switch needs to be run to the DME engine ECU in the engine bay. It needs to go into cavity #18 on connector x60001:



-



Pin/wire in cavity #3 on the clutch switch needs to be run to the CAS module cavity #3, connector X10318.

Pin/wire in cavity #4 on the clutch switch needs to be run to the CAS module cavity #41, connector X10318.



-



All of these pins SHOULD be missing in the CAS and DME. If they are already populated, we need to follow them and see if the car is possibly already pre wired which would be a total shocker BUT you never know.

Stay tuned!!

Yaw rate sensor, neutral sensor, fluid temp sensor, and reverse switch are next.
 
#74 ·
That looks identical to the clutch signal that is added during the E46 M3 smg -> manual swap.

I'm curious to see what would happen if you just recode the DME with the manual version (winkfp etc). On the E46 cars, you don't really have to run all the extra wiring to get the car running.
 
#76 · (Edited)
The next task is adding in the neutral sensor on top of the trans:



As with the clutch switch, this part does not exist in an SMG car from what I can see. HOPEFULLY whoever you buy your transmission from leaves this on to save you some money.

3 wires need to be run from this sensor directly to the DME engine ECU:



Here's the connector for the neutral sensor:





The pin/wire from cavity 1 goes to the DME connector X60002 from my previous post above, into cavity 6 in said connector.

The pin/wire from cavity 2 goes to the DME connector X60002 from my previous post above, into cavity 9 on the DME, and pin 3 on the neutral sensor goes to cavity 19 on the DME.

To simplify things with the transmission connectors you can use this harness:



BUT, if you go this route you still need to handle the female side of the big connector and its wires to the DME

 
#77 · (Edited)
The output shaft speed sensor exists in both SMG and 6MT cars, but pinning is slightly different

SMG:



6MT



Schematics above indicate that we need to remove the output shaft speed sensor signal wire from cavity 11 on the SMG ECU connector X70014, and move it to the DME connector x60002 into cavity 22.






The wire on pin #2 from the output shaft speed sensor needs to be spliced into the wire going into pin #1 on the neutral sensor pictured above in my earlier posts. This is the signal ground wire (Referred to as M_{masse}PKS in the scematics) for the transmission sensors.
 
#78 · (Edited)
Another major change is the yaw rate sensor...

In SMG cars it is wired directly to the SMG ECU, in 6MT cars it is wired directly to the DME. It's located under the front passenger seat:



SMG:



Pins 13 (yaw pin 3), 18 (yaw pin 1), and 20 (yaw pin 2) need removed from the SMG connector X53003.

6MT



Yaw pin 3 needs to go to cavity 11 on x60001 on DME

Yaw pin 1 needs to go to cavity 9 on x60001 on DME

Yaw pin 2 needs to go to cavity 10 on x60001 on DME
 
#79 · (Edited)
Lastly, the trans temp sensor, and reverse sensor.

Temp sensor:



Located on the bottom driver side of the transmission. Pin 2 needs run to DME pin 9 on the x60005 connector. Pin 1 wire needs run and spliced into the m_PKS wire on the neutral sensor.








Reverse switch:



Located on passenger rear bottom area of transmission.



Pin 2 on reverse switch needs run to pin 13 on the light module connector:





Pin 1 wire needs run to chassis ground somehwere
 
#81 · (Edited)
Day 1 was a moderate success!

My goal with this project is to gradually do as much of the legwork ahead of time that I can, this way the downtime is minimal. After all, this is my DD so i need it for the daily work commute.


Pedal assembly is here along with the hydraulic pipes for the clutch hydraulics:





It was cheaper to buy both pedals as an assembly than just the clutch pedal, SO, I decided to take a different route here. Removing and installing the pedal assembly is tricky due to the steering column motor being in the way so I decided to simply unmount the clutch parts from my used pedal on the bench, and reinstall them into my already installed pedal assembly in the footwell.






Another thing to note is that the SMG footwell shroud is not cut out for the clutch pedal. (Easy to fix with a dremel)



Foam is there



Pedal is in, and hydraulic hose is run through the firewall up to the brake fluid reservoir.



More to come :)
 
#414 ·
Day 1 was a moderate success!

My goal with this project is to gradually do as much of the legwork ahead of time that I can, this way the downtime is minimal. After all, this is my DD so i need it for the daily work commute.


Pedal assembly is here along with the hydraulic pipes for the clutch hydraulics:





It was cheaper to buy both pedals as an assembly than just the clutch pedal, SO, I decided to take a different route here. Removing and installing the pedal assembly is tricky due to the steering column motor being in the way so I decided to simply unmount the clutch parts from my used pedal on the bench, and reinstall them into my already installed pedal assembly in the footwell.






Another thing to note is that the SMG footwell shroud is not cut out for the clutch pedal. (Easy to fix with a dremel)



Foam is there



Pedal is in, and hydraulic hose is run through the firewall up to the brake fluid reservoir.



More to come :)
The BMW schematics for the x6021 are wrong when compared to the actual harness. The x6021 connector is shown as an 8 pin connector, but is actually a 12 pin connector when you get the harness. Because of this, none of the pinnings on the drawing for the trans harness sensors match the actual connector. I have manually veified each of the circuits with my multimeter, and illustrated everything below:



ACTUAL wire colors and cavity orientations coming from the original harness as arrived.

Hello Chariot.
Did you use all 8 cables with 0,5qmm in this connector X6012 ?
Thanks
Lubo
 
#82 · (Edited)
When pinning the clutch switch and running wires there is already a blue/black wire in the CAS in position 41. This wire is going to the SMG, so since the SMG ecu will be removed, you can repurpose this wire for pin 2 on your clutch switch. The other end of the wire can be removed from the SMG connector and relocated to position 18 on the DME where it needs to go.

No need to run additional wires into the engine bay if not necessary. :)
 
#84 ·
Thank you, thank you!

Shifter parts will be here tomorrow.

Actual cost so far:

Pedal assembly: $61.39
Shifter assy: $42.16
4 Hydraulic pipes: $153.05
Transmission: $1,380.20
New Clutch Kit: $400.38
New Flywheel: $449.78
 
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