AuroraGirl
I'm Awesome
no.I believe my (99 454) fan clutch studs are like that, although, I don't know the sizes. I was going to try to replace them, last time I had it apart, and all I could find was SAE that would be for your standard SBC of years past.
12338107 stud is M8X1.25X36
11516869 bolt (holding fan blade and fan clutch together) is M10X1.5X18 13THD 20 O.D. 9.8
11514602 nut (for the bolt above) is M8X1.25 6.8THK 13 O.D. 10.9
Not sure why gm has a 10.9 nut on a 9.8 bolt but who am i to judge.