BMW 550

Digest from the reviews

Based on transcripts of 2 reviews

• •Both of the 2 reviewed transcripts favor the F10 diesels — less hassle than the petrols — but the timing chains sit at the flywheel side and replacement is costly: across the two reviews N47 chains last ~100-200k km, N57/M57 ~250k km; one reviewer picks the post-2014 B47 if budget allows, while warning its EGR module can fail within 20-30k km.
• •The workshop transcript recalls the worldwide EGR-cooler recall on these diesels: cracked coolers let coolant meet soot in the intake and hundreds of cars burned — verify the recall was done; the other review adds that city-only crawling quickly kills the EGR and particulate filter, and a clogged EGR then damages the intake flaps.
• •Both treat the N20 2.0 turbo petrol (520i/528i) as liveable only with strict oil service: with ~10k km oil changes it can reach ~300k km, but both flag the oil-pump drive chain defect (snapped chains wrote engines off; fixed in 2014 — check the dealer fix on earlier cars) and spun rod bearings around 150-200k km; one adds chip-tuned 245-hp 520i units rarely pass ~120k km.
• •The ZF 8-speed is praised in both reviews but is not maintenance-free: change ATF every 50-60k km, watch the leak-prone plastic pan, and expect an overhaul at 150-250k km depending on version and driving style — an aggressive previous owner can kill the torque-converter lockup by ~100k km, so both advise a diagnostic scanner read-out before buying.
• •Both call the F10 body very rust-resistant with one caveat: the sealant at the steel-aluminium joints must be intact or galvanic corrosion becomes near-irreversible; cracked headlight-lens plastic is a known trait that costs the xenon units their sealing, and one reviewer warns most sellers wind back odometers — verify mileage independently.