1985 BMW 325 IX (E30). Black version

Launched in 1985, the E30 325iX was BMW’s first foray into all-wheel drive technology.

By 1985, the world hadn’t just grown used to the idea of four-wheel drive cars; they were clamouring for them. And while firms like Jensen, Subaru and AMC can all make their claims to bringing 4×4 to the average consumer, it was undoubtedly Audi’s Quattro system that had people’s blood pressure rising. The 325iX was built to tap that market.

The first models started out as standard chrome saloons in either 2- or 4-door flavours. They used the new 2.5-litre flavour of the M20 engine; the only lump with enough grunt to power the complex and heavy new drivetrain. By mating the standard engine and gearbox to a mechanical transfer box supplied by Ferguson, BMW were able to send separate drive shafts to the front and back of the car, sending power to all four wheels by way of two viscous differentials.

This system was both primitive and complex at the same time. The transfer case was outdated before it was released, but its simple mechanicals allowed BMW to set up a permanent rear-wheel bias to ensure the car still drive like a BMW. W

hen things got loose and wheels started to slip, the viscous differentials would kick in, locking anywhere between 10 and 100% without having to be manually locked by the driver. This meant that the car could transform from autobahn cruiser to off-road ranger in a heartbeat; perfect for the icy conditions of a European winter when every ounce of traction counts. Another boon was the weight; by crafting all the extras out of aluminium, the iX only weighs 80kg more than its two-wheel drive counterpart, and has both a wider track (13mm more) and taller ride hide (20mm) for better handling in adverse conditions.

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