Ever since I got my 240D, been bugged by a clashing 1-2 upshift. First, I found out the clutch master-slave were mismatched, the clutch engaged at about 1/4" off the floor. Fixed that with both units new and matched to application, then I changed fluid a few times. Dumped what was in there (red) for Dex III ATF, no joy. Tried Redline MTF, still no joy. Finally after doing some research on what MB recommended - ATF Type A, Suffix A, I found type F fit that bill. Walmart brand type F it shall be...
Didn't that fix it!?!

I've spent a few weeks making sure I wasn't imagining things, driving the car intermittently. No more grindy feel going 1-2. I went so far as to buy a full rebuild kit (piece by piece), and was prepared to pull the box. Who'd've thunk
I have to believe it's just a function of it being transmission fluid minus the friction modifiers that Dex III has in it. Lets the syncros grab the gear a bit better. I'll grab a win where I can find one!