You might want to begin by using the right tools for the job at hand. There are no Torx fasteners in any period Mercedes. They are XZN bolts. If you use a Torx bit, it will fit, but promptly strip out the head. First clean the head thoroughly and try the right bit. If that still doesn't work, you can try an extractor, although you may not have enough room. The last desperate solution is to grind off the head and remove the axle, then use a stud extractor or pipe wrench to remove the remaining stud.

^ This. It's not a torx. XZN aka "triple square" looks sort of like a torx, but it has 12 points instead of 6. Like Mxfrank said, If you used a torx, you done messed up...

Weld a nut to the mangled end and turn it out to extract. For re-installation, replace the damaged bolts, and don't attempt to torque them down with a torx socket or they'll just strip out immediately again.

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1998 E300 turbodiesel

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