Coming from a time when diesel engines were still a thing in the US, this X5 35d hides a secret. Since the SUV was built to US specifications, it has a single-turbo engine rather than the twin-turbo setup of its European counterpart. However, this is no ordinary F15 since its powertrain has been modified to extract considerably more power.

Wearing Stuttgart plates, the US-spec X5 35d dropped by the tuners at Darkside Developments in the UK to have its 3.0-liter engine upgraded. Indeed, the aftermarket specialist replaced the original turbo with a Garrett GTD2873VR turbocharger. In addition, the SUV received a beefier FMIC intercooler and a custom downpipe to unlock serious power from the oil-burner.

The dyno run shows over 600 pound-feet (814 Newton-meters) of torque and 413 horsepower. It still has the stock eight-speed ZF gearbox since it can easily handle the extra loads. We’ll remind you the stock X5 35d sold in North America had 255 hp and 413 lb-ft (560 Nm). Consequently, it’s no wonder this tuned version is way quicker.

This X5 35d Is No Slouch

In fact, the diesel monster hit 60 mph (96 km/h) in 4.66s and 100 mph (161 km/h) in 11.86s. Perhaps more impressive is the quarter-mile run in less than 13 seconds. It’s still a heavy vehicle with a diesel engine, and being an SUV, it doesn’t have the best drag coefficient. Obtaining these numbers wasn’t easy as customizing the ECU took a while, but Darkside Developers eventually cracked the code. There’s more to come as the tuner will work on the fuel system and camshafts in a bid to make the N57 even more powerful.

Being a 2016MY, this X5d was built near the end of the diesel BMW era in the US as all were dropped after the 2018MY. The decision was taken in the wake of the VW Group’s Dieselgate, which caused a massive drop in the demand for diesel cars.

Source: Darkside Developments / YouTube