How does the tire installer know the camber and castor is off? I'd much prefer to believe the computerized alignment machine than an offhand comment by a tire installer.
If both sides of a tire are worn down and the center of the tread is not, that tire has been ran underinflated/overloaded for a considerable time.
BTW, never cheap-out and get only a front-end alignment, pay for a total alignment so the entire vehicle is steering and tracking correctly. If the thrust angle is out much, when corrected you may notice a slight fuel mileage improvement along with the obvious benefits.
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2000 Winnebago Ultimate Freedom USQ40JD, ISC 8.3 Cummins 350, Spartan MM Chassis. USA 1SG, retired;PPA,Good Sam Life member,FMCA.
"We the people are the rightful masters of both the Congress and the Courts - not to overthrow the Constitution but to overthrow men who pervert the Constitution." Abraham Lincoln