I have a 1990 560 sel ran perfect , stopped car and next day no up shift at all. I can but it into B1 and then go back to D and feel the difference.
I can take the car up to 35-40 mph and release but still no upshift.
I checked the kickdown solenoid and powered it externally and it clicks;I don't know vacuum pressure but can feel vacuum at tranny. I can't afford to send it to a shop. So trying to do my own repairs as I have always done in the past.
HELP

If it is like the SD, it does not use vacuum to upshift. In fact you can disconnect the vac line from the tranny and it will upshift fine. Needs vac only for smooth downshift.

Check the fluid level. If it has been leaking, it will get to the point where it finally will almost refuse to upshift. I used to drive mine until that happened, turn around and drive home, fill it up with tranny fluid, and drive for about six months before it happened again. Very tough transmission; never hurt it and it always shifted perfectly smoothely after I put tranny fluid back in it.

Ihad a similiar problem a few years ago with same model car ,and knew it wasent aworn out tranny, so i removed valve body and started checking the valves or pistons in valve body, and found a sliver of metal jamming a valve , remove sliver of metal , put back together with new filter and car shifted normal afterwards, worth looking into.

I will look into it ; I never had taken a valve body so was hoping it would be something like a vacuum or wire or something like that.

it was just so weird to stop shifting so abruptly , you know working fine stop car and then no shifting..

seems like something happened when I stopped...at home...?weird