It only makes me think of a bad balancing really, quite strange...
I already had this problem once I drove in the mud and the balancing was bad because of mud on one side of the rims but I guess it can't be that in your case. Perhaps can you try without your hubcaps ? I really don't know
I already had this problem once I drove in the mud and the balancing was bad because of mud on one side of the rims but I guess it can't be that in your case. Perhaps can you try without your hubcaps ? I really don't know