E53 Alternator DIY

[ddjames]

The battery light of my '03 X5 (97K miles) came on last night on the way home from work. I pulled out the multimeter tonight and took the following measurements:

No load (battery disconnected): 11.77v
Engine off: 11.54v
Engine idling: 10.96v

The battery was replaced about 13 mo. ago and the belt (what I can see of it) looks to be in good condition. Other posts on this forum lead me to believe that it may be time to replace the alternator.

If anyone has a few minutes to answer some questions I'd really appreciate it!

Anyone know of a DIY for replacing the alternator? (BTW, Hayaku's DIY for CV boots by was fantastic!)

The alternator is barely viewable from the top of the engine. Is there no way to replace it from the bottom? Dropping the splash guard doesn't provide any usable access?

RealOEM lists several different units (90A / 120A / 140A / Bosch / Valeo). For purposes of ordering ahead of time, is there a way to determine which unit is installed prior to pulling it out?

Replacement alternators I've found from searching the web either come with or without pulley. Any pros/cons here?? Is the existing pulley difficult to remove or require special tools?

Any last words of encouragement (other than what's already posted)?

Thanks in advance. Keep up the great work!

~Dave