Grade 5 should be fine for the driveshaft bolts. I worked at Rockford
Products for 6 years making all diff. kinds of bolts and from what ive
learned, grade 5 bolts in that situation should be just fine. Grade 2 is too
weak and soft, grade 8 is fine but expensive, and 8.8 is too brittle and the
tensile strength isn't that high once you get that high in Carbon content.
You should be fine with Grade 5. Id use fine thread with a Nyloc nut on the
other end(which I did on my own car)..Hope that helps you out.
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