Fronts are floating & rears are fixed.

MB recommends replacing every bolt that they ship with loctite. If you buy the dealer front brake pad kit they ship it with TWO new bolts (ONE per side) beacuse in the shop manual you only remove one, then slide the caliper up or down to pull and reinstall the pads. The emergency brake kit from the dealer includes 4 new bolts for the rear calipers. MB is serious about replacing those bolts!!

But I know a lot of people who rarely or never change them and don't have problems.

Brian

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Brian Toscano