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IA Technical Bulletin

BMW N73 Engine Guide

Engine: N73

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N73 · 5,972 cc 60-degree V12 with Valvetronic and direct injection · BMW US-market cars built 01/2003 to 07/2008 · 760i and 760Li, plus the Rolls-Royce Phantom family in BMW's parts data

The N73B60 is BMW's 6.0 liter V12 (5,972 cc), a 60 degree engine that BMW's training calls a completely new development.

BMW's training says the first car was the E66 760Li, model year 2003, and that the 760Li was the version for the USA.

BMW's service information says the engine was first installed in March 2003, while its emissions data sheet gives production from 01/2003.

BMW's service information calls it the first direct injection on a BMW spark-ignition engine, and the training says it was also the first BMW engine to combine Valvetronic with direct injection.

BMW's training compares the N73B60 with the M73B54 V12.

BMW's service information says the engine was modified in 09/2006 as the N73TU to meet the LEV II limit for the USA.

BMW's data also contains an N73B68, whose displacement and output are not established here; the specifications below are for the N73B60.

Quick read

Ownership position: Not established yet. We are still researching this engine.
Reliability: No engine-wide verdict is established. One NHTSA recall names the engine in the 2003 760Li: 03V-324, the oil filter drain plug.
Cost to own: Not established yet. We are still researching this engine.
Power potential: Not established yet. We are still researching this engine. BMW's documents give the factory output as 320 kW, 327 kW or 445 hp, and 600 Nm at 3,950 rpm.
Main watch item: Not established yet. We are still researching this engine. Only the recall item below is backed by a BMW or NHTSA document.

N73 At a Glance

Question	Practical answer
Where it started	E66 760Li, model year 2003, per BMW's engine training.
Sold in US-market BMWs	Yes. BMW's parts data lists the 760i and the 760Li with the N73 engine code and US-market rows.
Factory output	600 Nm at 3,950 rpm. Power is 320 kW / 438 hp in BMW's training, 327 kW in BMW's emissions data sheet and 445 bhp in BMW's US model-update training.
Engine oil capacity	8.5 liters (9.0 US quarts) with a filter change, per BMW's training.
Engine oil	5W-30 LL01 or 0W-30 LL01FE, per BMW's February 2017 oil chart for model year 2011 and older gasoline engines. BMW's 2003 training recommended BMW High Performance 5W-30 synthetic oil.
Valve gear and fuel	Valvetronic, double VANOS, four valves per cylinder and direct fuel injection.
Firing order	1-7-5-11-3-9-6-12-2-8-4-10
Reliability profile	Not established yet. We are still researching this engine.
Best ownership indicator	Not established yet. We are still researching this engine.
Typical annual planning budget	Not established yet. We are still researching this engine.
Possible first-year catch-up	Not established yet. We are still researching this engine.
Largest documented exposure	NHTSA recall 03V-324 (oil filter drain plug torque, 2003 760Li). No repair costs are established.
Common tuned street range	Not established yet. We are still researching this engine.
Before buying	Confirm whether the car is a pre-09/2006 N73 or a later N73TU, and ask a BMW dealer to check the VIN for open recalls.

Where you find it

BMW's parts data lists the N73 in the US-market cars below. The parts data ends in December 2019, so later information is outside it.

Make	Chassis, model and build months (BMW parts data)
BMW	E65 760i 05/2004-09/2006; E66 760Li 01/2003-07/2008
Rolls-Royce, listed under the N73 code	Phantom 01/2003-04/2012 and 06/2012-11/2016; Phantom Extended Wheelbase 10/2006-02/2012 and 06/2012-11/2016
	Drophead 06/2007-02/2012 and 06/2012-12/2016; Coupe 08/2008-08/2011 and 06/2012-12/2016

The US start of the 760i is not settled: the parts rows begin in 05/2004, while BMW's emissions data sheet lists 760i and 760Li production from 01/2003.

The Rolls-Royce rows show the engine code only. The Rolls-Royce versions are not described by the BMW specifications below.

Technical Specifications

Values are for the N73B60 and come from BMW's training and service information.

Specification	Detail
Configuration	60 degree V12, four valves per cylinder
Displacement	5,972 cc, 89 x 80 mm bore and stroke
Compression ratio	11.3:1
Valves	Intake 35 mm and exhaust 29 mm valve diameter; intake lift 0.3-9.85 mm, exhaust lift 9.7 mm
Valvetrain	Valvetronic with double VANOS, intake adjustment range 63 degrees and exhaust 60 degrees, and a roller timing chain for each cylinder bank
Throttle	One throttle valve per bank that is not needed for load control, which Valvetronic handles
Fuel system	Direct injection at 50-120 bar
Engine management	Two MED 9.2.1 control units plus a Valvetronic control unit and two HDEV control units; MED 9.2.2 on the N73TU from 09/2006
Block	One-piece open-deck AluSil crankcase; magnesium intake manifold shell
Engine weight	280 kg
Maximum engine speed	6,500 rpm
Power and torque	600 Nm at 3,950 rpm; power 320 kW / 438 hp (training), 327 kW (emissions data sheet) or 445 bhp (US model-update training), all at 6,000 rpm
Oil capacity	8.5 liters (9.0 US quarts) with a filter change
Engine oil	BMW's February 2017 oil chart lists 5W-30 LL01 or 0W-30 LL01FE for all BMW gasoline engines of model year 2011 and older; the last US-market 760Li in BMW's parts data was built in 07/2008.
Coolant capacity	14.94 liters (15.8 US quarts)
Firing order	1-7-5-11-3-9-6-12-2-8-4-10

Factory Deep Dive

Valvetronic with direct injection

In BMW's service information, direct injection on the N73 is there for power and runs without a lean mixture, which lets the engine use a conventional three-way catalytic converter.

Valvetronic handles the fuel saving at part load.

Block, intake and timing drive

The block is a one-piece open-deck AluSil casting whose cylinder bores are etched to expose the silicon crystals.

The intake is a magnesium shell with a separate chamber for each cylinder bank.

BMW's training says two separate roller chains, one per bank, reduce the load on each chain, and the oil pump has its own roller chain.

The 09/2006 change (N73TU)

BMW's service information says the 09/2006 change brought MED 9.2.2 engine management, new processor and oxygen sensors, and the LEV II limit for the USA.

BMW's 2006 model-update training says the N73 remained unchanged for that update.

Service Parts at a Glance

BMW part numbers below were looked up in BMW's parts data and are the current numbers after supersession. Confirm fitment by VIN before ordering; a matching number locates a part but does not confirm fitment.

Part	BMW part number	Note
Oil filter element set	11427542021	760i, 760Li and the Rolls-Royce rows
Spark plug	12120037607	760i and 760Li
Ignition coil (Delphi)	12138616153	760i and 760Li
Ignition coil (Eldor)	12135A06753	760i and 760Li; replaces 12138657273 in BMW's chain
Thermostat	11537586885	760i and 760Li
Coolant pump, mechanical	11517586780	760i and 760Li
Timing chain	11318618318	760i and 760Li; replaces 11311439853 (discontinued 01/2015)

Known Failure Points and Service Items

Only items backed by an NHTSA recall record are listed. Everything else about N73 weak points is not established yet; see the research notes behind this guide.

01 Oil filter drain plug torque (2003 760Li)

NHTSA recall 03V-324 covers the 2003 745i, 745Li and 760Li, 2,400 vehicles; the N73 is the engine of the 760Li.

NHTSA's record says the engine oil filter drain plug may be insufficiently tightened, which could loosen it and cause an oil spray and then an oil leak. The remedy is for dealers to check the plug torque and retighten it to the specified value if necessary.

Watch for oil spray or an oil leak. NHTSA's consequence statement says a large oil loss could damage the engine.

No other recall naming the N73 engine was found in NHTSA's by-model records for the 760i and 760Li. That search was incomplete: some requests for the 760i returned errors, so treat it as a limit, not a clean result.

Reliability Verdict

Not established yet. We are still researching this engine.

Power Potential

Not established yet. We are still researching this engine. The factory output figures that BMW documents give are in Technical Specifications.

Cost of Ownership

Not established yet. We are still researching this engine.

Common Questions

What BMW models have the N73 engine?

In US-market BMWs, BMW's parts data lists the N73 in the E65 760i and the E66 760Li; the same data also lists it in the Rolls-Royce Phantom, Drophead and Coupe.

Does the N73 have direct injection?

Yes, BMW's service information says the N73B60 uses direct injection, and that it was the first BMW spark-ignition engine to do so.

How much oil does an N73 take?

BMW's training lists 8.5 liters, or 9.0 US quarts, for an oil change with a filter. BMW's February 2017 oil chart lists 5W-30 LL01 or 0W-30 LL01FE for these model years.