The 5.4-liter 12-cylinder BMW M73 or M73B54 engine was produced from 1994 to 2002 and was installed on the top models of the concern: the 7-Series sedan, 8-Series coupe and Rolls-Royce Silver Seraph. In 1998, an updated version of the motor appeared, it is distinguished by the index M73B54TU or M73TU.
The engine was installed on:
- BMW 7-Series E38 in 1994 – 2001;
- BMW 8-Series E31 in 1994 – 1999;
- Rolls-Royce Silver Seraph 1 in 1998 – 2002.
Specifications
| Production years | 1994-2002 |
| Displacement, cc | 5379 |
| Fuel system | distributed injection |
| Power output, hp | 326 |
| Torque output, Nm | 490 |
| Cylinder block | aluminum V12 |
| Block head | aluminum 24v |
| Cylinder bore, mm | 85 |
| Piston stroke, mm | 79 |
| Compression ratio | 10.0 |
| Features | no |
| Hydraulic lifters | yes |
| Timing drive | chain |
| Phase regulator | no |
| Turbocharging | no |
| Recommended engine oil | 5W-40 |
| Engine oil capacity, liter | 8.5 |
| Fuel type | petrol |
| Euro standards | EURO 3 |
| Fuel consumption, L/100 km (for BMW 750iL 1995) — city — highway — combined |
19.6 8.6 13.3 |
| Engine lifespan, km | ~350 000 |
Disadvantages of the M73B54 engine
- First of all, owners should not be embarrassed by fuel consumption of 20 liters per 100 km;
- The main reason for the unstable operation of the motor is air leakage in the intake;
- Closer to 200 – 250 thousand km, the timing chain often needs to be replaced along with sprockets;
- Also, on runs over 200,000 km, this power unit already decently consumes oil;
- Still here, leaks of the water pump or the rear crankshaft oil seal are often found.
