from the gorgeous 300sl goaling to the imposing 600 grocer and the timelessly elegant sl pagoda but for many people myself included mercedes hit their peak in 1975 with the introduction Of. of the comparatively humble w123 it was everything you could expect from a mercedes wellengineered comfortable refined and luxurious it was also bombproof reliable featured rugged dependable mechanicals and an Eclectic. eclectic lineup of engines and body styles it was a runaway success for mercedes and these days is a highly regarded and fast appreciating classic so if you want to get your hands on what might well be merc’s greatest hit here’s everything you need to know the w123 had fantastic quality paint and from 1980 particularly good quality rust proofing for its day but the Earliest. earliest examples of these cars are now knocking on for 50 years old and that means there’s still plenty of places where rust can and probably will Have. have developed by now for a start the wheel arches both front and rear get your hand up in here feel all the way around and make sure the arch shape is uniform smooth and well rounded all the way so that shows that it’s metal and not just Filler. filler you also want to check these rear spots here and when You’re. you’re around the front check the bottoms of The. the front wings because they can rot away As. as well they can get stone ships and that can build up to cause rot and rust over Time