, they have a speaker/component replacement guide. You just plug in your car's specs and it spits out what fits and what doesnt. Crutchfield's customer service is top notch for the DIY'ers. I looked just a min ago for your car, and looks like most all the replacements are 4" for the 10 speaker system, but they are not exact fits. I replaced my front speakers in my 1997 528 with a set of 5 1/4" component speakers. I also replaced my dash unit and added an amplifier and subwoofer. Lots of re-wiring, but it was definitely worth it as the tunes are 100% better. Not sure about the e60 sound system sounds stock, but my e39's just wasnt cutting it for me.