I am in the process of changing the brake disc on the ffront axles of my '79 450SL. The MB shop manual advises to also replace the self tightening bolts holding the disc to the hub but my old Haynes doesn't specifically say to do so.
My question is : Is it necessary to replace the bolts or will the old one work adequately?

kenny,
I do examine the tread condition of the old bolts, if its okay, I then re-use it and tightened within torque spe-cifications. I never experienced not much difference using the old ones. MB always recommends using a new one, ..if it is available,.....why not. Was it really required...?
Think about it......

The reason that MB recommends bolt replacement is the loctite(blue) that is encapulated onto the bolts. MOST braking componets get very hot & need loctite to keep them secured. THE bolts can be re-used if cleaned & fresh loctite is used. THERE are many who don't follow this practice & I have seen brake componets come loose due to lack of loctite.

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