BMW Secretly Increased Engine Displacement for 2015 X5

I am sure all consumers in the US know that, for the 35i trim of the 2015 BMW X5, they are still coming with the company’s famous N55 6-cylinder 3.0L turbo engine.

But perhaps unknown to most people, the N55 engine on the 2015 X5 sDrive35i and xDrive35i, is a different version that only exists in US-spec X5. In fact, even though they are named “3.0L” in all documents and advertisements, it does not mean an exact number of 3,000 cc. Specifically speaking, the N55 engines installed in all other BMW vehicles (except the 2015 X5 35i) have a displacement of 2,979 cc.


Starting from the 2015 model year, BMW is providing a special version of the N55 engine on 2015 X5 35i models, which increases the displacement by 25 cc. This means the 2015 X5 has an engine that displaces 3,004 cc. The change is only applied to X5 sold in US, the X5 35i models sold in other markets are still using the 2,979 cc displacement N55 engine.

Although the displacement is increased slightly, final horsepower output and torque rating has not changed. From my point of view there are two reasons behind this update:

1. BMW is using this as a platform to test some components for the N55 successor – the B57/58 twin-turbocharger engine

2. BMW is trying to discourage the act of exporting US-spec X5 to other markets in the world. Currently there is an incentive for people doing such things, due to different tax regulations between the US and other countries. Take China as example: for privately imported cars, if the engine displacement is less than 3,000 cc, then the tax rate is 12%; but if the engine displacement exceeded the 3,000 cc mark, the tax rate will immediately jump to at least 25%. So this makes importing a X5 from US to China more expensive, to the point that the total cost for such privately-imported X5 is not cheaper than the same model sold by BMW in China officially.

For more information about this change, please see page 26 of this BMW press release. is dedicated to bringing you the best, in depth news & reviews, techs & specs, throughout the auto industry. Visit and sign up today. 

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