I couldn't get hold of anyone making custom TCU for zf 8spd for bosch unit controlling the s85.

more accessible solution would be the dct from m3. same bolt pattern. everything will bold on. you'll need to tune the tcu for the dct yourself. then again, not sure if you'll find anyone that'll help you connect the tcu to the bosch ecu.

 

I couldn't get hold of anyone making custom TCU for zf 8spd for bosch unit controlling the s85.

more accessible solution would be the dct from m3. same bolt pattern. everything will bold on. you'll need to tune the tcu for the dct yourself. then again, not sure if you'll find anyone that'll help you connect the tcu to the bosch ecu.

So, either way its going to be difficult to be find someone who can put it together? I just figured that the zf is less than half the price than a dct so it would leave more room to budget for a tcu fabrication.

 

if saving a few dollars on zf is the draw, this isn't for you man. this will cost near 10k (possibly more), and you'll have to do the work & tuning mostly yourself. once it's all figured out, one can probably get the setup for 5k when DIY becomes available from a pioneer.

 

Just did a little more research on tcu options, turbo lamik makes one for the zf 8 hp's and has already successfully tested it on a 3 series. The parts to put the tcu together aren't expensive, but soldering is out of my element.

 

Why? We have the 6hp on my wife's diesel X5, and while I've flashed the TCU to a stage 2 to firm up shifts and remove torque limiting due to the increased power output but I wouldn't trade the SMG for that transmission for any reason whatsoever. It does a fine job in that application but is primitive in comparison to internet's "SMG III is trash" party-line...

 

There isn't as many options for TCU flashing and modding the SMG transmission, and the pump for the transmission is trash, but not the transmission itself. They are expensive to repair aswell so I figured I would go with a more reputable transmission, and there are parts everywhere for these things at lower costs than an SMG. Plus I would like to have the option to put it into park instead of having to use the e brake everytime.

 

Torque ok, The SMG III is rated for 8500 RPM.

 

So because your friends dump money on smg stuff (incompetent shop no doubt) they're garbage? I mean I'm not gonna say the SMG is bulletproof - but take @sunghyun7 for example. He thought about this exact same swap (8-sp auto) because his smg failed. Some back and forth troubleshooting and a $1 oring later his smg was fixed. My experience has been great - I've fixed / upgraded every weak link over time and has been pretty reliable with lots of track use (prob equates abuse for you).

What gave the smg its rep is the 99% shops out there who are unwilling (or worse, unable) to troubleshoot and want to just replace the whole smg unit and charge a $10k+ bill. Then there's the 99% of owners who are not DIYers and likely stuck dealing with above shops. Add the waves of cheap new young owners who can barely afford the car but owning a V10 is too hard to pass and... it is what it is.

 

So because your friends dump money on smg stuff (incompetent shop no doubt) they're garbage?

But I saw on "yung_rich_famous_hustle_dpmybutt"'s youtuve channel that they suck, Doug Demuro said it too for clicks and then 5 opinion webpages from people regurgitating what they read elsewhere that the smg is the worst transmission ever made yo. The E60/63 has become the uninformed auto-enthusiast's favorite click-bait, and through actual ownership and total self-repair it wasn't anything like I expected when I bought it.

Here's one, my 06 went 16 years and 106k miles before the SMG had any serious fault. It's smooth when I want to drive normal, rips the shifts off when I want it to as well. Sure, I'm dumping multiple thousands into it as we speak for a full rebuild/refresh - but again, it's an exotic drivetrain shoved in a german taxi, so "par for the course" also doesn't make it junk. This type of technology was used reliably in formula 1 for many years...

 

just fyi, my story is as follows:
1. smg stranded me under a bridge during rush hour. towed to my house
2. everything pointed to the hydraulic motor, so I changed hydraulic motor in my garage.
3. didn't work. I got busy and gave it to a shop to figure it out.
4. I found the highest rated shop in town based on forum & facebook reviews. the shop owner (over 50yo, works mostly on bmw's in his entire professional life) loved my car and said he can fix it.
5. after diagnosis, he says hydraulic motor needs to be replaced.. i said i already did that, but he said he's going to get brand new motor from the dealership. i said ok.
6. didn't fix it. now he said the accumulator needs to be replaced. i said ok.
7. didn't fix it. next step is new hydraulic block for $7k+ labor. i said no thanks and towed it back.
8. i looked into doing 8spd auto or dct swap. couldn't find anyone that can program me the TCU for e60 m5
9. flaco texted me picture of broken o-ring another member found on his smg.
10. i took down the transmission... hey guess what, broken o-ring. replaced and went on 1000+mile road trip without hiccup. now it's back to being my daily driver. TEN CENT O-RING literally almost totaled the e60 m5.

moral of the story is... this car is complicated and for most shops, they lack the expertise and experience to actually fix it. spending "thousands" rebuilding anything on this car is probably misguided.

 

just fyi, my story is as follows:
1. smg stranded me under a bridge during rush hour. towed to my house
2. everything pointed to the hydraulic motor, so I changed hydraulic motor in my garage.
3. didn't work. I got busy and gave it to a shop to figure it out.
4. I found the highest rated shop in town based on forum & facebook reviews. the shop owner (over 50yo, works mostly on bmw's in his entire professional life) loved my car and said he can fix it.
5. after diagnosis, he says hydraulic motor needs to be replaced.. i said i already did that, but he said he's going to get brand new motor from the dealership. i said ok.
6. didn't fix it. now he said the accumulator needs to be replaced. i said ok.
7. didn't fix it. next step is new hydraulic block for $7k+ labor. i said no thanks and towed it back.
8. i looked into doing 8spd auto or dct swap. couldn't find anyone that can program me the TCU for e60 m5
9. flaco texted me picture of broken o-ring another member found on his smg.
10. i took down the transmission... hey guess what, broken o-ring. replaced and went on 1000+mile road trip without hiccup. now it's back to being my daily driver. TEN CENT O-RING literally almost totaled the e60 m5.

moral of the story is... this car is complicated and for most shops, they lack the expertise and experience to actually fix it. spending "thousands" rebuilding anything on this car is probably misguided.

Hi, I am in exactly the same situation. Which is the o-ring you refer to?
(9. flaco texted me picture of broken o-ring another member found on his smg.)

Hydraulic Pump Seal's, have already been done.
Solenoid Valve Seal Kit?

Thanks,
Richard

 

@sunghyun7 in the shop's defense I also blamed the original motor to begin with. But accumulator nah no way I'd allowed that lol...

If not for this forum your story would've been another owners nightmare adding to the smg bad rep.

 

still can't believe 10cent oring almost totaled the car man. it basically became no-start and non-drivable due to broken o-ring..

thanks for your help! if you open up a shop rebuilding s85. i'll send mine in for refresh.

 

still can't believe 10cent oring almost totaled the car man. it basically became no-start and non-drivable due to broken o-ring..

thanks for your help! if you open up a shop rebuilding s85. i'll send mine in for refresh.

Thats for the solenoid next to the accumulator, right?

 

nah the clutch solenoid was ok. it was the o-ring for the solenoid sitting on top of the hydraulic block. i say do them everytime we do clutch.

 

These guys right?

 

These guys right?

Correct. Honestly tho if trans is out everyone should go through the whole thing. Pretty sure you've seen/heard/read the smg 'while in there to-do list' in the DIY sticky.

 

I would too love an ZF8, but the oil pump on them is limited to 8000rpm and I personally would like to keep all the revs I can, so for me it will be a DCT. A newer, wetclutch box should solve most of the 'problems' the SMG has.

On a sidenote, I have both an SMG3 car and a 6HP car. Although the 6HP is anything but sporty in an OEM configuration, with software like xHP on it, it is IMO much better than the SMG.

 

yes the solenoid o-rings. from all the pictures i saw, it's the rear facing solenoid o-rings. my front facing solenoid o-rings looked good. rear ones were shot with one broken. technically you can change them out with transmission still in the car (one guy already has done that on this forum). i wouldn't have attempted it personally, but since now we know it's possible (and it's been the rear solenoid o-rings that's broken), you can try it. worst case, the transmission isn't too hard to take down with 2 people. took about couple hours doing it the first time.

no need to get the kit. just buy it from the o-ring store or amazon. there's a post made by flaco that lists out o-ring dimensions. they are accurate. just get those in viton. you'll be fine. mine has been flawless.