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wheel spacers not fittinganother wheel spacer not fittingthreads are on the bottom half of the page this post is on
Basically there have been a couple cases where the inside diameter of the hub centric part of the spacer is too small. A machining error it would appear. Mine are snug, but with a lil antisieze it's not an issue. The spacers should fit on the hub, flush, without any use of the lugnuts to press it on. Likewise, the wheel should fit on the hub centric ring of the spacer without being pressed onto it by using the lugnuts.
Now the studs spinning could be a problem.
If it's the studs between the hub and the spacer you can take off the hub and cut out the stud from the back, or tack it and spin off the lugnut. After that replace the stud with a new one of same size or you're putting a stud with an oversize knurl in it if it damaged the hub.
If it's the stud that holds wheel to the spacer that's spinning, well, that's a whole special level of hell right there. You can't get to the backside of the stud to keep it from spinning (it's covered by the hub) and the studs on the spacers are threaded in for Marks spacers if I remember correctly, It would be incredibly tough to strip those... if he's moved to the knurled type its easier to strip, but either way, essentially the spacer is destroyed, there's no replacing the stud. Just getting the wheel off the vehicle without damaging it or the hub will be a challenge. For extra excitement you now have a wheel that's not securely fastened to the hub... I don't think anyone here would advocate you driving it despite most of us having seen plenty of cars rolling around missing lugnuts.
Either way, if you truly spun the studs you were likely using a pretty substantial amount of force to try to press the wheel, spacer, hub together.