535 manual transmission popping out of 1st.
 

2011 535i manual transmission, 100K miles, original tranny oil (I assume)

Car was fine, wife went away for 2 weeks, the car was not driven. She came back and now it pops out of 1st gear 50%+ of the time.

Research has pointed to 3 possible causes:
Bad/old/low tranny fluid
Bad tranny mounts
Bad 1st gear synchros

When accelerating in 1st gear the shifter seems to float a bit,maybe an inch of total of movement (tranny mounts?)
I had her try to stop, push in clutch, put in second then 1st, then release clutch and accelerate, she reported that it still popped (is this a valid test for synchros?)
I tried to hold it in 1st, it popped out and as I tried to hold it...... it just ground a bit and didnt engage. (points towards synchros?)


My plan of attack is to do fluid change and mounts and cross my fingers.

The first thing I need help with is finding the PN and quantity for the manual tranny mount bushings. Never heard of a single mount, but thats what the diagram looks like.
Real OEM says it is 22316770289. But when I search google for that number 99% tells me that it is for automatic transmissions. The others say auto and manual.
https://www.realoem.com/bmw/enUS/sho...diagId=22_0094

Can anyone confirm that the manual and auto tranny uses the same bushing? Any DIY's around for F10's Ive done them before on E10, E46, E34.... etc. But never a non round single mount.
I will keep everyone updated, hopefully this isnt a tranny rebuild :(

https://cimg4.ibsrv.net/gimg/5series...6317b883dd.jpg
https://cimg7.ibsrv.net/gimg/5series...aa6d26217d.jpg
Update
The tranny mount is indeed 22316770289 (same as auto), and a qty of 1. its just one large one in the middle
No DIY needed, remove 13mm nut on top and bottom of mount, raise tranny a bit, remove 13mm bolts that hold on cross bracket, take out bracket, replace mount....... reverse.

Changed fluid. Drained into a jug, then put an old hdd magnet in the jug and sloshed it around to grab all the metal that existed in the fluid. I then strained the fluid as i poured it out into a drain pan. Attached picture is the results.

At the end of the day, it still pops out of 1st gear :( F**Kety F** F**K!!!!!!

I will probably move this to a more general discussion since the only F10 issue was the PN.