Studs and Lugs

[PbFut]

Newer truck to me, I don’t recall my other trucks having lug nuts so tight. I’ve not had one of these trucks for more than 25yrs. Recently picked up a 72 GMC ¾ ton. The lug nuts and studs appear newer, no rust, blackened studs, normal looking lug nuts. 8 Lug, appear to be 9/16, I think. I can’t recall how the previous trucks were, but this one has lug nuts that seem way too tight. Almost like the pitch is ever so slightly off. The studs are black but after one or two on and offs, it seems they are in a way scrapping the blacking off the stud and the treads are bear metal and pretty bright. Nuts heat up when putting on and off do to friction and a fair amount of torque is needed to turn the nut off. It just does not seem right. Anyone run into this? Possible previous owner could have mixed SAE and metric? Not sure there is a SAE/Metric size this close. Any ideas?