[richardngriffin]

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