Pulled the spare to get the creative juices flowing for onboard air and I see this.......som biscuit FCA. You suck.
View attachment 4278
Frankly, it's rare these days that the spare matches the other wheels the vehicle ships with. I myself would never expect that the spare would be identical wheel & tire to the other four, unless the line-item description of a particular wheel & tire combo stated
specifically it would be
five of them.
I wouldn't want to pay for the extra cost of an expensive matching wheel, because the likelihood of using a spare tire these days is practically zero, and the money spent and the beauty of a matching wheel would just go wasted. The only thing I would care about is the strength of the wheel and the rating of the tire are sized to match the other wheels & tires, and the payload & towing capacity of a particular truck.
Those do not look like burns to me, they look like chafe/compression points where the spare was sucked up against the frame when the spare was raised into position. Maybe the mechanism raising the spare was over-torqued, I don't know. But if those were burns, I suspect the thin white lettering outlines would be black, not still white. The bluish tint is probably a bit of paint/coating that was on the undercarriage before the spare was sucked up against the frame and it simply transferred to the tire due to compression & vibration action as the truck was driven normally, or perhaps it is the mold-release agent on the tire itself, and it disappeared form the rest of the tire due to exposure to the elements underneath the truck, and the only place the mold-release agent remains is at the compression points with the frame.