[cbarlow]

I have a 2013 335i xDrive with 101K miles. The Production Date is 03/27/2013 and the In-Service Date is 04/26/2013. It's my daily driver.

I'm still running the original battery and the vehicle has not shown any indicators that I should replace it. BimmerApp shows capacity as 91 Ah and state of charge at 56%.

Do you guys think I'm playing with fire if I keep running it until a warning is displayed?

[obert]

I would just make sure I have the funds and then replace when it calls for it. I have already replaced mine but the car was asking for it.

[Billfitz]

Your main concern is winter, where the battery might not hold a charge well enough over night to start the car the next morning. I periodically use one of these to make sure it has at least 12v in the morning: https://www.amazon.com/Battery-Charg..._t1_B000EVWDU0

If it's marginal you can use a battery tender to nurse it along until it's convenient to change the battery. I use a tender throughout the winter, as I seldom drive more than one day a week, and then no more than 15 miles.

[lens]

Originally Posted by cbarlow

I have a 2013 335i xDrive with 101K miles. The Production Date is 03/27/2013 and the In-Service Date is 04/26/2013. It's my daily driver.

I'm still running the original battery and the vehicle has not shown any indicators that I should replace it. BimmerApp shows capacity as 91 Ah and state of charge at 56%.

Do you guys think I'm playing with fire if I keep running it until a warning is displayed?

Change it, mine went out in the end of winter (almost a 8 year old battery) it stopped holding charge randomly and would not crank anymore.

You can get a battery at costco with a 10 year warranty for like 2-300$

Might as well do it now before next winter hits.

Even if you use a battery tender, the cells might be damaged or so worn out that it will not hold the charge. When they tested my battery, it only had 200CCA out of 900CCA lol

[Orion4]

Probably very close to "end of life". Take car to an auto-parts store or Batteries Plus and have them conduct a "load Test". That will tell you how well the battery holds its charge when a significant drain is applied (like starting), etc. Some will also show the health of the cells.

[F32Fleet]

7 years is a good run. Replace it. They never fail at a good time.

I only say this because you're in Michigan.

[sspade]

No reason to replace it unless you're someone that consciously wastes money.

Of course, the second she starts fussing... you'll replace it.

In the meantime, do your research and have a source and model picked out so that its only a few clicks away.

[cbarlow]

I've already researched and shopped replacements. Here is my order of preference.

DieHard Platinum from Advance Auto Parts ($160)
Super Start Platinum from O'Reilly ($156)
Everstart Platinum from Walmart ($170)
Interstate AGM from Costco ($178)
Duralast from AutoZone ($190)
Champion AGM from Pep Boys ($155)

Many of these are probably the same exact battery, manufactured by either EnerSys or Johnson Controls.

[Billfitz]

Call the various sellers, ask if they have the necessary OBD diagnostic tool to register the battery. It's a must. Dealers charge up to $150 to do it, many auto supply outfits do it for free.

[cbarlow]

Originally Posted by Billfitz

Call the various sellers, ask if they have the necessary OBD diagnostic tool to register the battery. It's a must. Dealers charge up to $150 to do it, many auto supply outfits do it for free.

I have a Bluetooth ODB-II connector and the BimmerLink app which can be used to register the new battery.

[F32Fleet]

Originally Posted by cbarlow

I've already researched and shopped replacements. Here is my order of preference.

DieHard Platinum from Advance Auto Parts ($160)
Super Start Platinum from O'Reilly ($156)
Everstart Platinum from Walmart ($170)
Interstate AGM from Costco ($178)
Duralast from AutoZone ($190)
Champion AGM from Pep Boys ($155)

Many of these are probably the same exact battery, manufactured by either EnerSys or Johnson Controls.

Yes. There's only a couple of manufacturers for car batteries. Don't forget the build date. I've read that in some cases the batteries were charged and left sitting on a shelf for a year or more.

I wish we could by dead batteries and charge them at the time of purchase.

[thejeremyman9]

Originally Posted by F32Fleet

Yes. There's only a couple of manufacturers for car batteries. Don't forget the build date. I've read that in some cases the batteries were charged and left sitting on a shelf for a year or more.

I wish we could by dead batteries and charge them at the time of purchase.

+1 for checking build date. I went to buy a battery from autozone for my 3000gt once - also the AGM platinum (gray). He told me he was taking it in the back to test it. He comes out and the date sticker is gone. I asked the manufacturer date and he looks surprised i asked; turns out it was 1.5 years old and he was trying to hide that.

[bandook]

Yep I bought a battery from Batteries Plus and it was dead. Was borrowing the boss's Aston Martin for the weekend when the battery died. Car was locked in gear. So I picked up the new battery brought it home and went through all the trouble of putting the battery in, which these cars aren't easy It's buried behind the passenger seat, and it still want to start. Ended up needing to have it towed

[SaifaFox]

Glad someone mentioned build dates. I would have had no clue to check for that.