2015 BMW X5 with 35.6K miles; seeking preventive repairs advice

[cfm56d7b]

Our family vehicle - 2015 BMW X5 N55 xDrive - just crossed 35.6K miles.

It's a very low mileage vehicle and we plan to keep it. Repairs so far:

- Rear air springs
- AC evaporator

Brake fluid was flushed every 2 years. Oil changes done on schedule, every 6K miles.

Transmission fluid and all differential fluids are still original.

I just ordered aluminum N55 coolant flange from FCP Euro (big thanks to this community for the recommendation).

I am looking for additional preventive repairs recommendations. The first item on the list:

- Aluminum N55 charge pipe from Evolution Racewerks

Thank you in advance!

[tlow98]

Sounds like you’re covering most of the bases.

Two thing I’d mention:
- serpentine belt and tensioner. A failure here is nasty.
- transfer case fluid and calibration. It only holds 0.5 liters, gets dirty fast, and is an issue for a lot of people on here.

[cfm56d7b]

Originally Posted by tlow98

Sounds like you’re covering most of the bases.

Two thing I’d mention:
- serpentine belt and tensioner. A failure here is nasty.
- transfer case fluid and calibration. It only holds 0.5 liters, gets dirty fast, and is an issue for a lot of people on here.

tlow98 Thanks for the suggestions.

I was able to identify additional items:

- Serpentine belt + tensioner (as you mentioned) + idler

- Oil filter housing gasket

Thank you again for additional suggestions.

[yupetc]

You'll best also keep a keen eye and a sharp ear for weird ignition issues. In N55's DME, there aren't enough codes to cover ghost issues with the ignition coils and injector issues. So at times you may run into misfire codes and my experience with these is there could be a plethera of causes; sort of hard to figure out.

On every oil change, after you've completely get the job done, do run the engine to operating temperature and put the shifter to N or P and use the idrive menu to run a engine oil level reading. During this read, the eccentric shaft motor will go to work in controlling your throttle and stay at 1k rpms to measure the oil. If your car has issues with air leaks, VANOs, or eccentric cam control problems, you will likely not be able to complete the oil read because the rpm fluctuates out of range and idrive will just cut out. This is a good routine check I always perform for N55 motors. Was able to identify issues before they become severe enough to throw their own associated codes.

[menohuman]

It's hard to prevent most of the major issues. The serpentine belt problems are usually due to the tensioner or pulleys wearing out. Other times its due to the oil leaking from the valve cover.

A lot of times people go overboard but changing the fluids is the most important. Transmission fluid + filter, both differential fluids, transfer case fluids. I'd also change the coolant to the BMW HT-12 with a 60/40 mix and not the 50/50 mix the dealers and most shops do.

The almost guaranteed failure items, not included in preventive maintaince, before 125k miles are the water pump, OFHG, OPG, Valve Cover Gasket (BMW advises to replace the valve cover too due to warping), VANOS solenoids, belt and assembly, engine mounts.

[tlow98]

Originally Posted by menohuman

It's hard to prevent most of the major issues. The serpentine belt problems are usually due to the tensioner or pulleys wearing out. Other times its due to the oil leaking from the valve cover.

A lot of times people go overboard but changing the fluids is the most important. Transmission fluid + filter, both differential fluids, transfer case fluids. I'd also change the coolant to the BMW HT-12 with a 60/40 mix and not the 50/50 mix the dealers and most shops do.

The almost guaranteed failure items, not included in preventive maintaince, before 125k miles are the water pump, OFHG, OPG, Valve Cover Gasket (BMW advises to replace the valve cover too due to warping), VANOS solenoids, belt and assembly, engine mounts.

Good advice here. I’ve had almost all the components go that you mentioned.

Why the 60/40 mix, just curious?

[cfm56d7b]

Sharing an update: coolant flange replaced (ordered from FCP Euro), serpentine belt + pulleys also replaced.

The inspection revealed no leaks around oil filter housing.

Did anyone experience a charge pipe failure (lower or upper) on a stock engine? What was the mileage?