Introduction
The BMW 5 Series G30 (2017–2023) is the seventh generation of the executive sedan, the car that replaced the F10. It rides on the modular CLAR platform and shares a significant share of components with the 7 Series G11 and the 6 Series GT. The diesel 520d is the highest-volume version in the lineup and one of the most in-demand cars on the used market. Here’s what’s underneath, what breaks, and what to check before you commit to a deal.
Engine and Specifications
Under the hood, the 520d runs the B47 diesel: 2.0 liters, four cylinders, turbocharged. It replaced the N47, an engine with a habit of stretching its timing chain. Drive is rear-wheel or all-wheel xDrive.
| Spec | Value |
|---|---|
| Engine | 2.0 diesel, 4 cylinders, turbo (B47) |
| Power | 190 hp at 4,000 rpm |
| Torque | 295 lb-ft at 1,750–2,500 rpm |
| 0–60 mph | 7.3 s (rear-wheel drive) |
| Top speed | 146 mph |
| Fuel economy (claimed) | 47–52 mpg |
| CO2 emissions | 118–132 g/km |
| Curb weight | 1,635 kg |
| Trunk volume | 530 liters |
The claimed fuel economy diverges noticeably from reality—more on that below, in the real-world section.
Transmission
The standard fitment is the ZF 8HP automatic—an eight-speed unit considered one of the most reliable in its class. Some markets also got a 6-speed manual.
The ZF 8HP’s fluid gets changed roughly every 62,000 miles.
Suspension
The Dynamic Damper Control option—adaptive shock absorbers—is common across the trim range. At inspection, check them for oil leaks: replacement per axle is expensive.
Electronics and Equipment
The iDrive touchscreen at 10.25 or 12.3 inches (Professional Multimedia) is a clear step up from the base multimedia unit. Options worth hunting for: Navigator Pro, 4-zone climate control, the head-up display, power seats with memory, and folding mirrors.
Common Problems
Timing chain. That defect belongs to the N47 engine—the 520d of the previous F10 generation. The G30 carries the B47, where the problem is engineered out. On an imported car, verify the engine code separately: it must be B47, not N47.
TCB telematics battery. When it discharges, the instrument cluster throws an “SOS call not available” error. Check for it the first time you look through the cabin.
Active radiator grille. With the engine off, the upper and lower flaps should be closed. If the mechanism won’t close, aerodynamics suffer and the risk of overheating climbs.
Electrics and battery. Long stretches of sitting unused drain the battery and trigger false errors. Check the battery’s condition and that start-stop works.
FAP and AdBlue. In city driving, the particulate filter clogs up, and cleaning or replacement is expensive. Watch the warning lamps and the AdBlue level.
Cabin noises. Some owners report squeaks from the sunroof or trim—a test drive will surface them.
Contradictions in the Model Data
Three points in the source material don’t line up with each other—when you’re buying a specific car, verify each one separately.
First: the text ties the N47 in the 520d to production “up to 2015,” but that date doesn’t match the F10’s actual switch to the B47. The engine’s age has to be confirmed through the VIN of the specific car, not the model year of the vehicle.
Second: claimed consumption of 47–52 mpg against a real-world 34–39 mpg in the city. BMW’s number is more optimistic than what owners record.
Third: the performance verdicts diverge. What Car? rates the 520d as adequately brisk, while on PistonHeads owners complain the engine sounds strained and noisy during hard highway acceleration.
Pre-Purchase Inspection
- Priority goes to cars with the big screen (10.25/12.3 in) and a high level of equipment: nicer to live with and stronger at resale.
- Full service history, every service done on schedule.
- Mileage of 50,000–75,000 miles is normal. A high-mileage car without records is a reason to walk away.
- Use the VIN to confirm the engine is B47, not N47 (especially for cars imported from Germany and the UK).
- The VIN check will also show open recalls.
- No “SOS call not available” error on the instrument cluster.
- The active grille is closed with the car shut off.
- The adaptive dampers work and don’t leak.
- The battery is healthy and start-stop functions.
- No FAP warnings, and the AdBlue level is sufficient.
- Test drive: listen for sunroof and trim noises, and exercise every electronic function.
520d or 530d
The 530d gets the 6-cylinder diesel—more power and more refinement, but higher fuel burn and costlier to keep on the road. The 520d is more frugal, and for most uses that’s all you need.
Real-World Ownership
520d owners largely report moderate consumption: 39–47 mpg on the highway, 34–39 mpg in the city, and up to 52 mpg at a gentle pace. The G30 is quiet and planted, which is why buyers often pick it for long-distance travel. The 520d holds its resale value well.
The ZF 8HP has a reputation as very reliable. Ownership costs are shaped by genuine BMW parts and official BMW servicing—both expensive. The complex electronics produce the occasional sensor or iDrive glitch, but that’s the exception rather than the rule.
The Bottom Line
The 520d G30 is a strong used executive sedan: frugal engine, dependable automatic, high comfort. Before you commit, the key step is confirming by VIN that the engine under the hood is the B47, not the old N47, and that the car was serviced on schedule. Choose carefully and the purchase pays off.