e28_m5_early_exterior The E28 5 series was introduced in 1981. It was available as 4 door sedan. There were four models available: 518, 520i, 525i and 528i. All models received a better brake system from the E23 7 series and a service indicator. The 525i and 528i also received a check control and a double exhaust. In 1983 BMW introduced their first diesel ever: the 524td. It had a six cylinder diesel engine with 115 HP. In that same year a 525e was also introduced. In 1984 the 518 also received fuel injection...