A Brief Synopsis/Guide to the Auto -> 6-speed Swap

[Bryson]

This thread is intended to be a list of parts, steps, inside tricks, etc that need to be performed during the 6 speed conversion. This is not intended to be a mechanical guide including how to remove and install the parts, but it should provide you with everything you need to know before tackling the conversion.

I recently finished the conversion, and have it fully functional as stock, including no TRANS FAILSAFE error, working cruise control, 'S' display in the instrument cluster, and proper throttle control with the manual. Hopefully this will dispel the myth that a manual EML computer is required for the conversion. For clarification, I am currently using the automatic DMEs and EML computer.

Eventually, I will compile the information shared here into a proper DIY thread, but this is meant to be an open discussion before that point.

First, the parts list. In addition to this list, you will also need a clutch pedal assembly from an e31, e32 or e34, a clutch master cylinder (PN: 21-52-1-155-425), the soft clutch line to the reservoir (PN: 21521163714), and two firewall grommets (PNs: 21-52-1-156-082 and 21-52-1-159-206). The parts list does not include the exhaust mounts that bolt to the transmission (PNs: 18-30-1-723-518, 18-31-1-716-874, and 18-31-1-716-878, 2 each) or the 6-speed specific undertray splash guard (PN: 51-71-8-118-725).


Parts List

Description Part # Quantity List Price

Shifter Parts

Shifting Arm Upper 25-11-1-221-576 1 $40.72
Bearing, Shifter arm 25-11-1-221-581 1 $27.60
Bolt, Shifter Arm 07-11-9-915-047 2 $0.38
Selector Rod, lower 25-11-1-221-577 1 $56.68
Shift Rod Joint 25-11-7-503-525 1 $37.51
Securing Clip 25-11-7-571-899 2 $0.66
Plastic Washer 25-11-1-220-439 4 $0.25
Bitch clip, Left 25-11-1-221-579 1 $11.80
Bitch clip, Right 25-11-1-221-580 1 $11.80
Shifter bush (round) 25-11-1-221-578 2 $7.65
Shifter bush (oval) 25-11-7-519-670 2 $2.89 (My shift carrier took these, not the above. I ordered both for cheap insurance)
Plastic shift cup 25-11-1-220-600 1 $10.33
Rubber inner shift boot 25-11-1-220-785 1 $16.18

Shift Lever 25-11-7-527-253 1 $69.02 (Z3 2.8L/3.0L)
Short Shift Lever 25-11-7-527-254 1 $69.98 (MZ3, 25% reduction in throw, replaces above. recommended)

Gearbox Mounting/Suspension

Cross Member 23-70-1-137-868 1 $45.88
Tranny mount 23-70-1-137-870 1 $161.44
Tranny mount flange 23-70-1-137-869 1 $89.64
Bolt w/ washer 22-32-6-760-945 4 $1.10
Flat washer 07-11-9-931-096 2 $2.56
Hex nut 07-11-9-922-857 2 $0.73
Hex bolt w/ washer 07-11-9-915-093 2 $0.51

Torx Bolt 23-00-1-222-888 8 $1.58
Flat washer 07-11-9-931-698 8 $0.40
Torx Bolt 23-00-1-222-887 2 $1.15
Flat washer 07-11-9-931-660 2 $0.40
Hex Nut 07-11-9-922-857 2 $0.73
Wave washer 07-11-9-932-112 2 $0.09
Dowel 23-11-1-606-156 2 $9.53

Driveline

Driveshaft 26-11-1-226-673 1 $919.37
Center Guide Bush 26-11-1-226-696 1 $11.35
Guibo (110mm/14) 26-11-1-227-419 0 $128.27
CSi Guibo (110mm/14) 26-11-2-227-577 1 $136.73 (I used this with CSi driveshaft, replaces above)
Hex Bolt 26-11-1-227-829 6 $3.62
Guibo Nut 26-11-1-227-830 6 $1.38

Clutch

Clutch Kit 21-21-1-223-413 1 $876.50
Flywheel 11-22-1-736-395 1 $669.54
Flywheel Bolts 11-22-1-717-841 9 $2.43
Pilot Bearing 11-21-1-720-310 1 $23.65
Slave Cyl 21-52-1-161-874 1 $185.16
Slave pipe @ slave 21-52-1-159-392 1 $12.25
Slave pipe long 21-52-1-159-565 1 $65.79
Nuts for slave 07-12-9-906-196 4 $1.64
Studs for slave 21-51-1-203-012 2 $4.03
Pivot pin 21-51-1-223-281 1 $24.60
Fork Lever 21-51-1-204-229 1 $14.08
Fork retaining clip 21-51-7-570-284 1 $4.77
Pressure plate bolt 07-11-9-919-939 6 $0.38

Total before tax

$3666.96

Electrical

The electrical involvement is required in only three places of the car:

Starter

In order to get the starter to fire, two terminals must be jumped across the starter relay. This is exactly how the factory performed this operation. The photo below depicts the jumper (red wire) that replaces the removed relay directly above it.

Trans Fail Safe Program warning elimination

In order to keep the car from giving a TRANS FAILSAFE PROG error every time you start it up, you must ground pin 9 of connector X506 [located behind and to the right of the HVAC display panel, it is a white 12 pin plug]. (Picture to come)

Cruise Control and Throttle Control

In order to have functional cruise control and proper EML throttle adaptation, you must ground pins 4 and 5 of connector X18055 [located behind and to the right of the HVAC display panel, it is a black 12 pin plug]. Additionally, this can be performed at the DMEs (pins 63 and 64), or the EGS transmission computer (pins 24 and 25). (Picture to come)

Location of X506:


Picture of X506 before making jumper harness (the red wire in the photo is the power wire for my V1 radar detector:

and finally, a somewhat organized series of photos during my conversion, taken straight from the old 6-speed swap thread:

Here's what a factory fresh Getrag S6S 560G looks like







I had some spare time this afternoon, so I pulled out the automagic and replaced it with a real man's transmission..



Excuse the white powder all over the trim pieces, I had just taken off a pair of nitrile powdered gloves. Unfortunately I also forgot to take a picture of the UUC cerametallic clutch going in :/



If you were wondering what the difference between auto and CSi driveshafts is, here you go:


The CSi (possibly all manuals?) uses a larger CV joint at the diff than the automatic and is the same length. I ended up using the rear portion of my stock driveshaft and the front portion of the CSi mated together.

boxes full of many parts


here you can see where I performed surgery on my mufflers to do the 'Dinan exhaust mod'


The underside of the car with the exhaust removed


The shift console coming apart


The transmission as installed


The complete shifter assembly installed


Close up on the shift selector


Another close up of the shift selector with the output shaft


The back of the tranny with the modified driveshaft and CSi flexdisc installed


The center support carrier, to the left of the carrier is the CSi portion of the driveshaft, and to the right is the 850iA portion


And a shot of the flange at the diff. My CV boot is torn, so it looks like that driveshaft rebuild will be needed very soon



Please comment and add to my list if you have any information (Randy ), I'll do my best to recall any more small details in the meantime.

[olinjohnston]

Great! Now do one for the 840

[8eights]

Awesome post!

[ChrisFuture8]

Crazy, wild, and awesome mod, Bryson. You didn't take pictures of the surgery under the hood and clutch pedal installation? I don't see the clutch pedal assembly in your parts list.

Cheers,

Chris

[cer54467]

Yes Brayson please a few more pics, this is in my future

[Sully51]

That parts list cost doesn't even include the ~$2500 trans right?

I really want to do this but I'm not sure I can justify 6 grand

[Winks]

Looks good, I would love to do that to mine.....

[crazy8]

AWESOME. Thanks for the post.

[crazy8]

That parts list cost doesn't even include the ~$2500 trans right?

I really want to do this but I'm not sure I can justify 6 grand

Yes, I believe so, but a used unit out of a 540 can be had for much cheaper. Worth it IMHO

[Sully51]

I thought the V12 could only use the V12 specific trans. Ideally I'd find one in the junkyard with almost all the parts needed, that's a pipe dream though

You v8 guys can do it on the cheap, haha

[olinjohnston]

Yes, I believe so, but a used unit out of a 540 can be had for much cheaper. Worth it IMHO

Only for us V8s. The 850 uses a special one shared with no other car.

[cer54467]

Only for us V8s. The 850 uses a special one shared with no other car.

I am not positive but to me the only difference is; & i have 2 other six speeds in my dirveway is the addition of a pair of mounts mid section. and one on the set up i just purchased has been broke for a long time.

[revtor]

I am not positive but to me the only difference is; & i have 2 other six speeds in my dirveway is the addition of a pair of mounts mid section. and one on the set up i just purchased has been broke for a long time.

The V12 gearbox has a much higher torque rating than the V8 gearbox (S6S 560G = 560 Nm and S6S 420G = 420 Nm according to the BMW numbering system). But knowing these Germans, the gearboxes probably have a huge safety margin and the fact that BMW put the S6S 420G in the 500 Nm E39 M5 and Z8 suggests that it shouldn't have problems with the torque delivered by the 850i and 850Ci. The 850CSi or a turbo/supercharged 8 Series may be stretching it...

[rcrad6653]

For those of you seriously contemplating this change, these numbers are real. Yes to do it right it's north of $6 grand. You can certainly do it cheaper with a parts car...... I even have spares/extras. The new transmission units popping up won't be $2500, but believe me the smoothness you get from shifts is worth it. Mine's the only one I've ever driven that doesn't have that 1st/2nd 'catch'.

I recommend doing a short shift kit while there..... IMO this mod should be considered essential.

A 3.15 diff has the most votes by manual owners as what to use and keep the car practical. Add the differential cost to the Swap ($300-2300)

Rebuilding a drivshaft is about 50% less than buying a new OEM one.

[Tonn]

...BMW put the S6S 420G in the 500 Nm E39 M5 and Z8 suggests that it shouldn't have problems with the torque delivered by the 850i and 850Ci. The 850CSi or a turbo/supercharged 8 Series may be stretching it...

There are some twin supercharged/turbocharged ~800hp e39 M5s running around, no idea if or how the transmissions hold up though.

[tonys]

Great post. Thanks for the effort!

The TRANS FAILSAFE error you work around is only due to the lack of the shift lock solenoid, yes?

Tony

[cdnalpina]

Awesome write-up and resource, thanks for posting all this Brandon. Maybe one day I'll get around to doing this...

[cer54467]

How many hours do you have in the install with out the the searching for parts?

[cer54467]

There are some twin supercharged/turbocharged ~800hp e39 M5s running around, no idea if or how the transmissions hold up though.

Would you have the link for the twin turbo cars?

[Bryson]

For those of you seriously contemplating this change, these numbers are real. Yes to do it right it's north of $6 grand. You can certainly do it cheaper with a parts car...... I even have spares/extras. The new transmission units popping up won't be $2500, but believe me the smoothness you get from shifts is worth it. Mine's the only one I've ever driven that doesn't have that 1st/2nd 'catch'.

I recommend doing a short shift kit while there..... IMO this mod should be considered essential.

A 3.15 diff has the most votes by manual owners as what to use and keep the car practical. Add the differential cost to the Swap ($300-2300)

Rebuilding a drivshaft is about 50% less than buying a new OEM one.

Good points. All said and done, the conversion cost me about $4k with more than half being the new transmission. Creative parts sourcing was absolutely key in keeping the cost down, so keep your eyes open for deals.

The short shift kit (I would recommend an MZ3 or Z4 shift lever if you want to try an OEM SSK) and 3.15LSD are a very nice combination with the gearbox, I'll have to add these notes to the original post.

There are some twin supercharged/turbocharged ~800hp e39 M5s running around, no idea if or how the transmissions hold up though.

I hear that those M5s frequently go through second gears and have to replace the transmissions. I loosely follow some of the big power e39 M5s on M5Board and other websites.

Great post. Thanks for the effort!

The TRANS FAILSAFE error you work around is only due to the lack of the shift lock solenoid, yes?

Tony

The trans failsafe error comes up because there is no EGS computer to send the 'all clear' [ground] signal anymore. I can't tell you if it's just the shift lock solenoid or a combination of whatever things the EGS computer monitors.

How many hours do you have in the install with out the the searching for parts?

I had about 12 hours in the mechanical swap, and probably a little more into figuring out the wiring issues. I actually finished the conversion almost exactly 24 hours after I started.

[cer54467]

[/QUOTE]
I hear that those M5s frequently go through second gears and have to replace the transmissions. I loosely follow some of the big power e39 M5s on M5Board and other websites.
[/QUOTE]

Not to side track this thread but the second in my M5 is kinda touch to get into untill the car is warmed up, On my 540 it is like butter.... Just SMooooooth. I am thinking i need to chage fluid as i think someone put the worng stuff in it. it has a short shifter in it.

Man i wish i had soemone else close buy that could give a hand.... this back pain stuff really sucks!

[Imndeep]

Wow Bryson, badass write up. Thank you.

[rcrad6653]

A note on the pedals... you don't need the complete pedal assembly for the swap. It's nonsense to remove the steering column to put in a whole assembly. The pedal chassis is the same, auto or stick. You need the pedals, a longer bolt for two pedals, the return spring, and the cruise cutout switch. That's it.... you leave the chassis alone. You can do the pedal swap and hook up the brakes and keep driving the car. Nearly the whole interior swap process can be complete before disabling the car.

[whiteghost1]

Excellent writeup. Hopefully it will come in handy for a 6spd swap in my 750iL Individual........one day.

Any other pics of your 'Dinan exhaust mod' - what was done to accomplish this? Is it just a matter of removing a couple of extra internal baffles? How's the sound?

Thanks!

[Bryson]

This info would certainly apply for an e32 6 speed conversion. Shifter parts and driveshaft would be almost certainly different, however.

The dinan exhaust mod involves removing a "U" bend inside the muffler. Sounds like stock with just a little more depth to the exhaust. I love it, I'm not too into loud m70s, I think they sound really awful