Often cited by BMW enthusiasts as a high point for the 5 Series — a genuinely well-engineered executive saloon where the M54's cooling system is, once again, the main thing worth budgeting for.
The E39's midsize executive body carries the straight-six comfortably, with a ride and handling balance that's held up remarkably well against newer rivals — a large part of this generation's enduring reputation.
Earlier cars in this range used the preceding M52 engine rather than the M54; the two share much of the same cooling-system risk profile, so the same checks broadly apply either way.
This is about the car itself — for engine-specific failure points, see the dedicated engine page below.
This generation of 5 Series shares much of its cooling-system risk profile with the related M54 used in the E46. Full engine detail lives on the dedicated engine page.
FULL ENGINE BREAKDOWNBMW M54 Straight-Six — Reliable or Not →Ask whether the cooling system has been upgraded to metal/aluminium replacement parts, the same key check as on the related E46.
If the car has self-leveling rear suspension, test it by loading the boot and checking the ride height response.
Inspect sills, subframes and wheel arches closely for rust, a genuine risk at this age in harsher climates.