Posted by Keith on Wednesday, November 29, 2006 at 10:55AM :
In Reply to: Type of Bolts? posted by Roger in Louisiana on Tuesday, November 28, 2006 at 3:44PM :
For brakes, suspension, steering and winches, I go with Grade 8. Note too what fasteners OEMs go with in these locations. For example, I've yet to see an OEM use a Grade 5 bolt to mount a steering box to a frame.
As to Grade 8 vs Grade 5, sheer strength is 60% of tensile strength as a working safety factor (See page 4 of http://www.fastenal.com/content/documents/FastenalTechnicalReferenceGuide.pdf), and Grade 8 will have a higher tensile strength than Grade 5 in every case. See page 36 of http://www.fastenal.com/content/documents/FastenalTechnicalReferenceGuide.pdf.
As to use on 4x4's a good write up can be found at http://www.pirate4x4.com/tech/billavista/NutsandBolts/Nuts&Bolts_signed.pdf