Maintenance Schedule beyond Factory Maintenance

[jereisluke]

My 2014 E84 28i ran out of factory warranty and maintenance recently and I'm trying to put together a master schedule for maintenance so I know when to replace what and don't have to worry too much about it. I've got the basics covered based on the manual (oil, cabin/air filters, spark plugs, brake pads/fluid) but wanted to get input on some items not discussed in the manual.

At what mileage do you think these things below should be replaced? I'm using mileage instead of years/time since mine is a daily driver and mileage just seems to make more sense. I looked at Bavarian Autosport’s E91 schedule (https://www.bavauto.com/media/import...ages/e91mc.pdf) as a starting point, but they have a very conservative schedule (more $ for them from people buying parts). I can share the master schedule when it's finished too if anyone is interested.

• Fuel filter? 60K? (Manual doesn’t even mention this for some reason, does BMW not think this needs to be replaced?)
  
• Automatic transmission fluid and filter? 75K? BMW says this is a lifetime fluid, but I don’t buy it.
  
• Differential fluid? 75K? BMW says this is a lifetime fluid, but I don’t buy it.
  
• Coolant? 50K? BMW says this is a lifetime fluid, but I don’t buy it.
  
• Shocks/struts & other suspension parts? 60K or just replace when worn?
  
• Timing chain? 100K? Or does it need to be replaced at all if chain/guides have been upgraded from old failure prone version?
  
• Drive belts? 60K or just replace when worn?

[mreric]

I have attached the ZF transmission instruction from the manufacturer

according to the manufacturer the tranny fluid should be done at no more than 75K

as for the other stuff... i am not sure..

[thestimp]

I'm at 80k miles and I'm doing all these things this fall. From what I've read people either say "if you can afford it do it" or, "Its lifetime dont worry". Just pulling the trigger since I plan on having the car another year or 2.

[Chicone]

As part of this I'm curious how many years factory batteries are lasting before needing replacement. I suppose there are a lot of variables, hotter climates, how long it sat on the lot etc.

Usually at 5 years I start to worry, for me that means next year, but I have not seen any issues yet, but have only had the car a couple months.

-Steve

2015 X1 XDrive MSport //BMS Intake

[Turbod]

My BMW dealer said "lifetime fluid" is rated at 100,000 miles. My battery went out on my 335i six years after the build date. I would do your diff when you do the transmission. I would do your coolant when you replace the water pump and thermostat. Suspension is completely up to the driver. I would look to do the timing chain between 100,000 and 120,000. As for the belt system I have heard horror stories about the N55 eating the belt through the crank seal. I don't know if that is an issue for the N20 though. Most N55's are replacing them between 60,000 and 80,000 miles.

[mcdanielvzw]

Originally Posted by Chicone

As part of this I'm curious how many years factory batteries are lasting before needing replacement. I suppose there are a lot of variables, hotter climates, how long it sat on the lot etc.

Usually at 5 years I start to worry, for me that means next year, but I have not seen any issues yet, but have only had the car a couple months.

-Steve

2015 X1 XDrive MSport //BMS Intake

5 years for any battery is a lot of time, however I believe companies like tesla went from a 5 to 7 year warranty because they only use 80% of the total capacity, hence they last longer. You still lose range, but it's far less than doing a 0-100 charge every time.

If you mean car batteries, before BMW I looked for replacements every 3-4 years (battery in engine bay with my Mazda 6). I've had good dealing with BMW batteries being in the trunk so far, but haven't had the opportunity to pass the 3-4 year mark as of yet with a single battery. AGMs should last longer of course.

[jereisluke]

Thanks all for the input so far. That's interesting that the BMW dealer basically told you that lifetime fluid doesn't really mean lifetime fluid.

[Turbod]

Originally Posted by jereisluke

Thanks all for the input so far. That's interesting that the BMW dealer basically told you that lifetime fluid doesn't really mean lifetime fluid.

Because only a company would tell you it is. Anyone with any knowledge knows there is no such thing as lifetime fluid. Glad I could help.

[bvanlieu]

Originally Posted by jereisluke

Thanks all for the input so far. That's interesting that the BMW dealer basically told you that lifetime fluid doesn't really mean lifetime fluid.

Dealers with a clue are aware of this fact. Most US customers never drive their cars this far, so from a point of view it is a life time. BMW lifetime is semantically 100K miles.

All that being said, good plan to do the fluids 60-75K range. IMHO transmission is the biggest one to do: ZF makes a good transmission, and I trust them a bit more then BMW on the maint interval. Most kits come with the Mechatronic sleeve but to me if that is dry leave it be no need to replace. No affiliation, I used https://www.thectsc.com/ for their kit on the 335d. ZF fluid is more but I am fine with that, if not there are a few other fluids that carry the same spec.

While its up in the air, do not forget the transfer case fluid. Its not a lot of fluid, but it is a PITA to get to on the X Drives.

Our N55 just crossed 62K and I plan on doing the driveline fluid change within a year.

- b

[Gamb1t]

Pretty sure there is a thread topic on maintenance here. If not check the F30 section.

As for the tranny fluid, I noticed that my local BMW dealership sells fluid and filter kits for our ZF8 despite the whole "lifetime fluid". Interestingly the service dept. refuses to perform the change unless there's something wrong with the tranny.

My car is at about 77k km and I've done all fluid changes except tranny. Will tackle that at 100k km. Or sooner. So far the only tricky one I've experienced is the xfer case fluid. There is a thread about it that I have appended my thoughts and tips.

Modern BMWs come with AGM batteries. They are more advanced than the regular lead ones and are able to cope with the electronic stress associated with modern European cars. That said one of the SA I spoke with told me that weak battery can lead to faulty/false alarm sensor codes. It is a good idea to keep a batter tender and charge the AGM battery every so often to keep it healthy.

[Chicone]

Originally Posted by Gamb1t

Modern BMWs come with AGM batteries. They are more advanced than the regular lead ones and are able to cope with the electronic stress associated with modern European cars. e the AGM battery every so often to keep it healthy.

Thanks! I had no idea, having driven my last car for 19 years, and a new BMW owner I was unaware of this innovation. Was a bit shocking when I googled it and saw the battery prices.

-Steve

2015 BMW X! 35i MSport // BMS Intake

[Gamb1t]

Originally Posted by Chicone

Thanks! I had no idea, having driven my last car for 19 years, and a new BMW owner I was unaware of this innovation. Was a bit shocking when I googled it and saw the battery prices.

-Steve

2015 BMW X! 35i MSport // BMS Intake

Yes AGM batteries are about twice the price of a regular ones. It also costs more with BMW requiring an ECU adaptation values to be reset whenever you change a new battery. Reason is so that the ECU will not tell the alternator to over-compensate for your old battery. It's cha-ching for the dealership. More reason to keep your current AGM battery healthy. I've seen some AGMs lasting 10 years with proper conditioning.
BTW that ECU reset can be done through the iCarly app.