There are a few different types of rear axles used on the cars covered in this guide. A solid rear axle is used on 1977-81 200SX, 710, and all station wagon models. The 1978-81 510 uses a solid rear axle with either coil springs or leaf springs, depending on whether it is a sedan or a wagon. Independent rear suspension (IRS) is used on the 610 sedans, 810/Maxima sedan (some models use solid rear axle). In this (IRS) design separate axle driveshafts are used to transmit power from the differential to the wheels.