At the 1986 Turin Auto Salon, a prototype 75 estate was to be seen, an attractive forerunner of the later 156 Sportwagon. This version was, however, nixed after Fiat took control of Alfa Romeo. The car, dubbed the 75 Turbo Wagon, was made by Italian coachbuilder Rayton Fissore using a 75 Turbo as the basis.Two estate versions were to be found at the later 1987 Geneva Motor Show; one was this Turbo Wagon and the other was a 2.0 litre version named the Sportwagon.
The 75 featured some unusual technical features, most notably the fact that it was almost perfectly balanced from front to rear.This was achieved by using Transaxle schema - mounting the standard five-speed gearbox in the rear connected to the rear differential (rear-wheel drive). The front suspension was a torsion bar and shock absorber combination and the rear an expensive De Dion tube assembled with shock absorbers; these designs were intended to optimize the car's handling; moreover the rear brake discs were fitted at the centre of the rear axle, near the gearbox-differential group. The engine crankshaft was bolted directly to the two-segment driveshaft which ran the length of the underside from the engine block to the gearbox, and rotated at the speed of the engine. The shaft segments were joined with elastomeric 'doughnuts' to prevent vibration and engine/gearbox damage. The 2.0 L Twin Spark and the 3.0 Litre V6 were equipped with limited slip differential.
The 75 featured a then advanced dashboard-mounted diagnostic computer, called Alfa Romeo Control, capable of monitoring the engine systems and alerting the drivers of potential faults.
The 75 engine range at launch featured four-cylinder 1.6, 1.8 and 2.0 liter petrol carbureted engines, a 2.0 liter intercooled turbodiesel made by VM Motori, and a 2.5 liter fuel injected V6. In 1986 was introduced 75 Turbo, which featured fuel injected 1779 cc twin cam engine using Garrett T3 turbocharger, intercooler and oil cooler.
In 1987, a 3.0 liter V6 was added to the range and the 2.0 L Alfa Romeo Twin Cam engine was redesigned to have now two spark plugs per cylinder, the engine was named as Twin Spark. With fuel injection and variable valve timing this engine produced 148 bhp.In North America, where the car was known as the Milano, only the 2.5 and 3.0 V6s were available, from 1987 to 1989.