Engine reliability, rated
Every engine in the guide gets a published reliability rating out of 100, argued for on the method page. It is one input to each car's reliability score, alongside the car's own known problems, service costs and age.
| Engine | Rating | Cars in this guide |
|---|---|---|
| B58 | 92 Excellent | M240i F22, Z4 M40i G29, M340i G20, M240i F23, M340i G20 facelift, M240i G42, M440i G22 / G26 facelift, M440i G22 / G26, X3 M40i G01, X4 M40i G02, X3 M50 G45, M440i G23 facelift, M440i G23 |
| S58 | 85 Strong | M2 G87, M4 G82, M3 G80, M4 G83, X3 M F97, X4 M F98 |
| B48 | 84 Strong | X1 M35i U11, X2 M35i U10, X2 M35i F39, M235i Gran Coupe F44, M235 Gran Coupe F74 |
| S50 | 80 Strong | M3 E36 |
| S52 | 80 Strong | M Roadster and M Coupe E36/7, M3 E36 |
| S65 | 78 Good | M3 E92 |
| N55 | 76 Good | M2 F87, M235i F22, X4 M40i F26 |
| S14 | 72 Good | M3 E30 |
| S38 | 72 Good | M5 E28, M6 E24, M5 E34 |
| S55 | 72 Good | M2 F87, M4 F82, M3 F80, M4 F83 |
| S62 | 72 Good | M5 E39 |
| eDrive | 70 Good | i4 M50 G26, i7 M70 G70, i5 M60 G60, iX M60 I20 |
| S54 | 70 Good | M3 E46, M Roadster and M Coupe E36/7, Z4 M E85 |
| S63 | 68 Moderate | M5 F90, M8 F92 / F91 / F93, M5 F10, M6 F13, X6 M F96, X5 M F95, X5 M F85, X6 M F86, X6 M E71, X5 M E70 |
| S68 | 66 Moderate | M5 G90 / G99, X6 M F96, X5 M F95, XM G09, X5 M50i and M60i G05, X7 M50i and M60i G07, X6 M50i and M60i G06 |
| N63 | 65 Moderate | M550i G30 facelift, M550i G30, M850i G15, M850i G15 facelift, M850i G14 facelift, M850i G14, X5 M50i and M60i G05, X7 M50i and M60i G07, X6 M50i and M60i G06 |
| N54 | 62 Moderate | 1 Series M E82 |
| N74 | 60 Moderate | M760i G12 |
| S85 | 55 Mixed | M5 E60, M6 E63 |