Main Drive Belt

Hi Does anyone have a view as to when the alternator and the aircon belts should be changed? They seem to be in good condition but would consider doing it as a preventative measure.
thanks

Belts typically last about 60K miles. You can easily check their condition using a bright flashlight. Look for small cracks or a shiny surface, which always develop long before the belt fails.

I was told by my BMW service rep, the the belts on BMW can easily go over 100K miles and he has yet to see one car come in with broken belts under 100K miles. I changed mine at 90K, because my serpentine belt got noisy. It started whining because oil got on it.

So how do you change these belts

Sent from my Transformer TF101 using Bimmer

You will need a sepentine belt tool w/ a large Torx socket T-55. To remove the sepentine belt first (lest than 10 minutes) Take a picture of the belt before removing it so you know how it goes back on.
Jack up the car and remove the front underbody cover. You use a towel to remove the A/C compressor belt while turning the crank/engine. One you remove the old A/C belt, put the new belt over the crank first, and then install it on the bottom of the A/C compressor and install the tool pictured on the A/C compressor pulley. Turn the crank clockwise keeping the belt tight and the tool will pop the belt on. I had to do it twice because the belt ribs did not line up the first time.

I need to do a DIY on the job.

I attached the BMW PDFs for both jobs in the previous post.

BTW, use OEM belts. They last over 100K miles. I used a aftermarket A/C belt and it shredded in under a month.

Hope this helps!