[Michael C Henry]

My experince isn't so intense. I worked for a local marine deisel repair for a short time many years ago.. I came away with an attitude adjustment ,If the manufacture doesn't put their name or mark on the head of a bolt, I won't use it.If Catapilar built it it has the best bolts available ,they even have better than normal sheet metal screws.
No name bolts that are bought by the pound are not worth carring out of the store. the only plus is they are easy to drill out.
OEM car manufactures use mostly grade 5 bolts in less critical areas..A grade 8 bolt under stress in a part with out a good washer is not relieable either. The part can fail and the fastener can still be in place undamged.Then it becomes a design or assembly issue. I chose to replace many of the bolts when in the process with ARP bolts.In critical areas it was black steel, in lesser areas like intake manifold and valve covers it was their SS bolts. For hood and dash I used SS fasteners supplied by local store. I'm sure that grade 8 national fine 3/8" bolts in the windsheild supports are overkill. The 2 legs of the windsheild braces will give up first.
I'd be more concerned with OEM and salvaged parts being used that are not up to the application.Also the best bolt in place and not tight is not much better than a lesser bolt that is correctly tightened.
All thing being consideced we could form a heck of a pannel of experts ? I work on Army heavey mobile equipment.