Originally Posted by BimmerM3inGA

So it's been a bad week for the fleet. On my way to work Wednesday morning, I got a flat in my nearly new 2015 i3. No spare tire, and non-runflat tires mean waiting an hour for Roadside Assistance on the shoulder of I-75. Then, the next day the X5 4.6is that's been kicking my ass for the last 9 months stuck again. There was a very loud sound from under the hood and the engine would die if I let its speed drop to an idle.

Not wanting to attempt diagnosis in nice clothes (the wife and I were on our way to dinner), and not wanting to risk further damage, I called for a tow and waited another hour for the tow truck to arrive and drag its sorry carcass back to the house.

The problem this time is the alternator. The bearings are very rough and it's very difficult to spin the pulley. I've been doing some research and it seems that the bearing failure is fairly common, and the bearings themselves are available from BMW.

Has anyone tried this repair? What were the results? Is it worth it to spend $40 on a set a bearings, or should I just order a newly rebuilt Bosch alternator?