86 240 dl sedan automatic w/OD 160k

The back-story: I had recently noticed the "whining" (referred to in a number of other threads here) - high pitched, during accel/decelleration when i hit 45mph - give or take... the last time i noticed it, an extra can of oil (synth)subsided the noise. Well, it began whining again (about two months between) - so, i went for gas and oil...

The incident: After fueling up and adding some oil (10-W-30) I pulled onto the road, noticing some serious exhaust smoke and at the top of 1st gear the engine began chattering hard. I could tell it wasn't going to shift past 1, so i pulled off and parked.

Now: The rig will start, smoke a little, drive around the parking lot in first and chatter if i push it... idles fine aside from exhaust and i can shift through 1,2,D,N,R and P - reverse, drive and first all function (with above issues) decided not to test 2.

Is this a drive shaft bearing issue and it just happened to go at that time - or does it stem from the mix of synth/oil (there is no foaming or gumming in the oil mixture)- or do i have a much larger issue at hand?

AK winter is coming in quickly - any suggestions would be much appreciated