Who says the aftermarket wheels were actually built to OEM specs?



For what it's worth, steel for wheels is a specific grade with high fatigue resistance. Cornering wheels flex, and repeated flexing can lead to cracks, if the metallurgy isn't right. Flexing is why lost hubcaps mostly congregate at intersections. A wheel maker who wants this steel must buy it in melt lots of around 50 tons. This quantity of raw material shouldn't be a problem for a company in the wheel business, but you have to wonder if an unknown maker's raw materials purchasing standards are up to snuff.

The same grade of steel is also used to make cooling fan hubs. Same repeated flexing in service. Don't stand beside the fan when an engine is reving...