BMW N63 engine explained: the twin-turbo V8, its versions and known issues

The BMW N63 is the 4.4-litre twin-turbo V8 that BMW introduced in 2008. It was the first production engine with its turbochargers placed inside the V of the engine, a layout BMW calls hot V, and it powered models such as the 550i, 650i, 750i, X5 xDrive50i and X6 xDrive50i.

The N63 is strong and smooth, but the early versions have a reputation for some issues. In this guide we explain the BMW N63, its versions, known problems and what to check.

What makes the BMW N63 special

In most V engines, the exhaust manifolds and turbochargers sit on the outside of the cylinder banks. In the N63, BMW turned the cylinder heads around: the exhaust ports face into the V, and the two turbochargers sit between the banks.

This hot-V layout has several benefits:

• Short exhaust paths, so the turbos respond quickly.
• A compact engine, which fits more easily in the engine bay.
• Fast catalyst warm-up, which helps emissions.

The drawback is heat. Turbochargers, exhaust parts and catalytic converters all sit in the middle of the engine, which places high thermal loads on surrounding parts such as seals and hoses.

Versions of the N63

The N63 was developed over several generations:

• N63 (from 2008): the first version, with about 400 PS in most models.
• N63TU (from about 2012): a major update with Valvetronic, revised turbos and cooling, and more power, around 450 PS.
• Later updates (from about 2016 and 2018): further changes to the turbos, cooling and electronics, with power up to around 530 PS in some models.

The M version of this engine family is the S63, used in M5, M6, X5 M and X6 M models. Our article on the BMW S63 engine explains it. The newer S68 V8 continues the idea with mild hybrid support, as our BMW S68 engine article explains.

Known issues of the BMW N63

The early N63 in particular has some well-known issues:

• Oil consumption, often linked to valve stem seals and the heat in the V.
• Timing chain wear, especially on engines with long oil change intervals. Our article on BMW timing chain problems explains the risk.
• Fuel injectors, which were updated several times.
• Coolant and oil leaks from hoses and seals exposed to heat.
• Battery and electrical issues caused by high demand.

BMW released service actions and updates for the N63 in several markets, sometimes called a customer care package, with shorter oil change intervals and replaced parts. Later versions improved many of these points.

Maintenance for a healthy N63

Preventive maintenance is the key with this engine:

• Shorter oil change intervals than the original long intervals, using the correct BMW-approved oil.
• Check oil consumption regularly and keep the level correct. Our article on BMW oil consumption explains what is normal.
• Keep the cooling system in good condition, because the engine runs hot inside the V.
• Let the engine warm up gently and avoid switching off immediately after hard driving, so the turbos can cool.
• Update the software and complete open recalls at a BMW dealer.

With good care, many N63 engines cover high mileages without major problems.

Buying a used BMW with the N63

When buying a car with an N63, check:

• Full service history, ideally with shorter oil change intervals.
• Evidence of completed service actions and recalls.
• Oil consumption and signs of smoke at start-up. Our article on BMW exhaust smoke explains what the colours mean.
• Leaks around the engine and the turbos.
• Cold-start noise that may indicate timing chain wear.

Later N63TU engines are generally a safer choice than the first versions. A pre-purchase inspection by a BMW specialist is strongly recommended. Our guides to the F15 and G05 X5 and the F01 7 Series cover these cars.

Is the N63 a good engine?

The N63 delivers what a big BMW needs: strong, smooth power, a pleasant V8 sound and excellent performance in large saloons and SUVs. Its weak points come mostly from the heat of the hot-V design and from long service intervals in the early years.

Later versions and cars maintained with shorter oil intervals are far less troublesome. For buyers, the most important factor is not the engine code but the history and condition of the individual car.

If you prefer fewer risks, a six-cylinder such as the B58 can be a sensible alternative. Our article on the N54 vs N55 vs B58 compares BMW six-cylinder engines.

BMW N63 at a glance

Item	Details
Engine	BMW N63 twin-turbo V8
Displacement	About 4.4 litres
Layout	Hot V: turbochargers inside the V
Introduced	2008 (X6 xDrive50i)
Power	About 400 PS (early) up to about 530 PS (later)
Main updates	N63TU from about 2012 with Valvetronic
Used in	550i, 650i, 750i, X5 and X6 50i, and others
Known issues	Oil use, timing chains, injectors, heat-related leaks
M version	S63

Frequently asked questions

What cars use the BMW N63 engine?

Models such as the 550i, 650i, 750i, X5 xDrive50i, X6 xDrive50i and later M550i and M850i variants, depending on the year and version.

Is the BMW N63 reliable?

The early versions are known for oil consumption, timing chain wear and injector issues. Later versions are better, and good maintenance with shorter oil intervals makes a big difference.

What is the BMW hot-V layout?

The turbochargers sit inside the V between the two cylinder banks, with the exhaust ports facing inwards. This gives quick turbo response and a compact engine, but more heat in the middle of the engine.

What is the difference between the N63 and the S63?

The S63 is the BMW M version of this V8 family, with more power, stronger parts and M-specific cooling and lubrication.

Should I buy a car with an N63?

It can be a good choice if the car has a full history, shorter oil change intervals and completed service actions. Later N63TU engines are generally a safer choice than the first versions.

Sources

• BMW Group PressClub – V8 engine press material
• BMW Group – recalls and service actions
• BMW owner's manuals – engine oil and maintenance