M Buyers Guide

Inspection checklist

M850i G15 facelift, 2023 to 2026

Printed October 29, 2026. Tick each item at the viewing, and write down what you find.

Before you go

  • Open recalls. Run the VIN through NHTSA or a BMW dealer and ask for proof every recall was done.
  • History report. Check the title, accidents, owners and mileage record.
  • Service records. Ask for them in advance, ideally from a BMW dealer or specialist.
  • Certified or not. BMW can still certify 2023 to 2026 cars. If this one is certified, ask for the paperwork showing when its cover ends.
  • Independent inspection. Book a pre-purchase inspection with a shop that knows this engine.

Known problems on this car

  • Oil and coolant leaks about $1,500 to fix

    Inspect for leaks at valve covers, turbo oil lines, and the cooling system.

  • Cooling system load about $1,500 to fix

    Verify cooling parts have been refreshed past 80k mi, ask if owner has run 5k to 7.5k oil intervals.

  • Oil consumption about $1,500 to fix

    Ask owner about oil top-ups between changes, review service records.

  • Valve stem seals about $4,000 to fix

    Look for blue startup smoke, request a leakdown on high mileage cars.

At the viewing

Same as the pre-LCI: oil consumption history, cooling system status, full records with shorter oil intervals, no accident history. Check that the illuminated grille works. On 2023 cars, check that recalls 23V-099 and 23V-821 are done.

Notes

From the M850i G15 facelift guide at M Buyers Guide. Repair costs are the guide's estimates, not quotes; the guide says where each comes from. Problems and costs as of the date printed.