What mileage should the alternator be replaced on your vehicle?

[David_Smith2003]

Has anyone had to change their BMW's alternator, and if so, at what mileage?

The battery in my car is the original one, and it has been there for about 132,500 miles. Not sure if it would be better to replace it right away or wait. I do not do many miles.

Thoughts?

[AstonMartinLover]

Mrs. vehicle has 180k miles on it and still has the original alternator. I'd leave well alone until it fails and keep the cash in your pocket.

[Sarah_Jane1980]

Replace the brushes instead, since this is a low-cost option that does not need taking apart the alternator.

[David_Smith2003]

Replace the brushes instead, since this is a low-cost option that does not need taking apart the alternator.

A few years ago, I considered replacing the brushes but didn't realise it could be done while the car was still on the ground. As my health is deteriorating, it would be simpler to replace the entire apparatus.

[John_Doe1975]

I had an E39 diesel car that I sold with 368k miles on it and the original generator. As said, don't touch it until you need to.
cheers

[BentleyOwner]

E61 5 Series (M47TU2D20) alternator changed at 206,000 miles. It required upgrading since voltage spikes caused numerous components to shut down to prevent harm (dash lighting up with all kinds of warning lights!).

[Rebecca_Taylor90]

Due to voltage spikes, I changed the voltage regulator and brushes on my 145,000. I was nervous, but it was extremely simple and took me about 30-45 minutes to complete.

[Samantha_Jones83]

The complete unit should be replaced, yes.
The bearings were worn when I changed the brushes.

[Rebecca_Taylor90]

The complete unit should be replaced, yes.
The bearings were worn when I changed the brushes.

While I agree in theory, the price differential between the regulator and the whole alternator should be considered.