Why BMW's twin-turbo V8 needs a new battery with every oil change

[lanbrown]

My battery lasted about 4.5 years. Keep in mind that while BMW will replace a battery every oil change but not in under 12 months; so someone could drive 1,000 miles a month and they would keep a battery for 20 months. This only applies to the N63 vehicles and how many are under the original warranty/maintenance? Many are coming off of warranty/maintenance now and BMW will not be replacing the battery in those.

BMW is taking the proactive approach in making sure the battery issue doesn't arise. It is not like they are paying $500 for the battery. They are getting those batteries at a pretty cheap price and the labor is not all that expensive either. The customer is already in the shop getting service done and performing a battery coding is quick. My estimates, they are paying under $150 if not under $125 for a battery replacement, so even if someone got one a year, that is $500 to $600 that BMW paid. Many vehicles will never see our batteries paid by BMW though. Many 2011's probably never saw a battery from BMW with the rest just one. 2012's probably will see 1 maybe 2. 2013's will see 2 maybe 3. 2014's would be 3 to 4.

[Ron07x5]

Originally Posted by BGM

I wonder if BMW replaces the battery after you are out of warranty for the lifetime of the car?

Good.question! I wonder.why they don't change the charging software algorithm it.seems.crazy.to have the system engage.the alternator.to charge.the battery when the battery.falls.below 75 percent? Fine let.it.do it's.I.Will.charge.when coasting.only.but once that.isn't happening.then fall.back.to.what.Will.guarantee.reliability and battery life! I am a.firmware.engineer.and.this seems obvious to me. So I assume.there is.some.other.factor I do not.know about like .... if.they charged.at.75 then mpg.might be higher and.later.the.epa mpg and.then there could be.legal repercussions?

[Ron07x5]

Originally Posted by trader4

What I said was:

"It doesn't mean every one needs new batteries at 10K,
but BMW for sure isn't changing them at 10K if it's not a real,
significant problem with a lot of them."

Meaning according to the article, BMW is changing them at 10K miles
and therefore it seems BMW must believe it's a real, significant problem with a lot of them.

What an expense.for bmw and.a.risk.and.hassle.for.owners. why won't they just change software algorithm? Then for users that coast a fair amount car charging works as it presently.does and where users do not.coast must the system charges battery when needed not just when coasting. Why not?