Update: This simply could be a test mule for the European market and not an indication that the X3 30d is coming to the US.

Our friend and spy photographer Palbay just spotted the first BMW X3 3.0 diesel on U.S. soil. The diesel prototype was spotted in the Spartanburg area and makes for an interesting find since BMW currently only offers the xDrive35d model in North America.

BMW has yet to announce any plans of introducing an X3 diesel in the U.S. and these photos will create even more speculations around future models in the X3 line-up. The test mule spotted also features the aggressive and sporty looking M Sport Package, but with a different choice of wheels from the one shown in official photos and at the Paris Motor Show.

The 3.0 liter diesel engine found in the X3 xDrive30d made its debut this past year when the F10 530d went on sale. and shortly after BMW began offering the turbocharged 3.0-liter inline-six engine in the X5 xDrive30d model.

Last December, BMW announced that the X3 xDrive30d will debut in Europe this spring. With the 3.0 liter straight-six engine, the X3 xDrive30d outputs 245 horsepower and 400 lb-ft of torque, flat-lining from 1750 through to 3000 rpm. It has an all-aluminum crankcase, common rail direct injection of the last generation and a thermodynamically optimized turbocharger with variable intake geometry. The fuel is up to 1,800 bar placed in the combustion chambers, which allows for particularly efficient combustion.

The turbo diesel engine helps the X3 accelerate to 100 km/h in 6.2 seconds and a maximum speed of 155 mph. Thanks to BMW BluePerformance technology it fulfills the EU6 emission standard and it offers impressive fuel consumption, 6.0 liters per 100 km, approximately 39.2 mpg and CO2 emissions of 159 grams.

In the U.S., BMW has only one diesel engine that passed all the 50 States emission regulations, and that is the 3.0 liter twin-turbo diesel found in the 335d and X5 35d models. It is unclear at the moment if BMW is pursuing the homologation of a new diesel powerplant or this is simply a prototype used as a test bed.