low voltage question

I was driving along today and i noticed that my alternator started dying... on the way from the autroparts store, two things happened: my abs inop light came on and my transmission would NOT shift to the overdrive gear. The voltage was VERY low. it was all up in the red! im gonna change it tonight, but i was wondering about the trasnny and if maybe that had something to do with the low voltage. I had checked my tranny fluid and the level was ok, but it was very bubbly.... is this ok? also it was very hot outside if that helps.

Bubbly trans fluid usually is a indicator that it is overfilled.

And when the charging system is not up to snuff, alot of the systems are affected on newer cars, abs, trac, and recently I dealt with a passlock problem caused by a low charged battery.

ok.. cool can't have too much right? ;). but really, if thats a problem how do i drain a little bit?

syphon or drop the pan.