Maintenance chart · 2012–2020
BMW 3 / 4 Series — F30 / F32
Four very different engines under one body. Know which one you have — the schedule below does.
328i / 428i — N20/N26 2.0T
Engine
— BMW's condition-based interval was written for lease cycles, not second owners — half of it is what keeps timing components and turbos alive past 100k.Book an appointment →
— Plugs mask themselves behind adaptive coils on these engines — by the time you feel the misfire, you're two steps past the fix.Book an appointment →
— Early N20 chain guides are this platform's defining failure — a whine from the back of the engine is a stop-driving conversation, and we check for it at every service.Book an appointment →
— Direct injection across the board here — we scope first, photograph what we find, and blast only when the deposits justify it.Book an appointment →
— The classic BMW seep — and on this engine bay the filter-housing leak drips onto the belt, which is how a gasket becomes a shredded belt behind the crank seal.Book an appointment →
— Twenty minutes with a solenoid beats a week of guessing at cam-timing codes — it's the first thing we rule out.Book an appointment →
— The factory plastic charge pipe cracks at the throttle-body neck, stock or tuned — the aluminum replacement costs less than one tow.Book an appointment →
Cooling
— These pumps fail electrically, without warning, and usually in traffic — at 80k we consider replacement maintenance, not repair.Book an appointment →
— Fresh coolant and a pressure test every 60k is how plastic BMW cooling parts make it to 150k instead of failing at 90.Book an appointment →
Transmission
— ZF itself calls for service by eight years or 100k — "lifetime fill" means the transmission's lifetime, which neglect shortens.Book an appointment →
— Gear oil is the cheapest synchro repair there is.Book an appointment →
Drivetrain
— The xDrive transfer case in particular runs a small fluid volume very hard — 60k keeps its clutch pack honest.Book an appointment →
Brakes
— One of the few places the factory book already says what we'd say.Book an appointment →
— The wear sensor is one wire on one axle — we measure all four corners instead of trusting it.
Suspension
— F30 steering feel lives in the front guide joints — when the car starts wandering on the highway, this is usually why.
Engineering notes
Known issues on this platform
N20/N26 timing chain & oil-pump drive failure
Chain guides embrittle and let go, and the oil-pump drive chain can follow — a whine from the rear of the engine is the warning. Caught early it's a chain kit; ignored, it's an engine. We listen for it at every visit on every N20.
Timing chain & guide replacement
Electric water pump failure — N20/N55
No weep, no warning — the pump simply stops and the temperature spikes inside a mile. Proactive replacement by 80k is cheaper than the aluminum head that overheating risks.
Water pump & thermostat replacement
Oil filter housing gasket → belt failure chain
The housing gasket leaks onto the serpentine belt; oil-soaked belts shred, and the debris can be drawn behind the crank pulley toward the front main seal. A simple gasket caught early prevents the whole cascade.
Housing gasket & belt service
Valve-cover & PCV leaks
The plastic valve cover and integrated PCV bake with heat cycles — smoke smell after highway pulls and oil on the exhaust manifold are the tells.
Valve cover & gasket replacement
Intake-valve carbon buildup
All four engines are direct-injection. Rough cold idle and soft midrange are the symptoms; the borescope tells the truth in five minutes.
Walnut-blast carbon cleaning
Charge-pipe failure — N20/N55
The plastic charge pipe cracks at its throttle-body neck and the car goes limp mid-drive. The aluminum upgrade is standard practice on every tuned car we touch.
Charge-pipe upgrade
BMW 3 / 4 Series — F30 / F32
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