some of those tempa-spare wheels I wouldnt trust on a dolly...at work we made wheels for a mid 80's tbird tempaspare- was a nice Alcoa forging, but was so freaking flimsy you could bend them by hand...drilling the lugholes and valvestems we used to break drills as the flange would 'snap' back as the drill point broke thru...one ofthe thinnest wheels we ever ran and had to putt with the cycle times to machine it.
I'm sure the steel wheels are a bit stronger, but as they are not required to meet normal load ratings, I doubt if they do.

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