Douglas-
While I don't know what the specifications are for passenger wheels, FWIW, the
spec for aluminum wheels on Medium and Heavy Duty trucks is .030
(thirty-thousandths) or less. We have found in truck tires and wheels,
drivers can't feel it if the total assembly runout is less than .045-.050 (max
industry tolerance = .095). Of course, we're talking about a significantly
heavier assembly, but still, it's pretty tight for aluminum wheels (steel
wheels are allowed .070).
A runout gauge / magnetic base is pretty cheap from most tool shops. The
roller bearing that mounts on the tip (mostly used for tires) can easily
exceed the $30 stand and gauge combo. Test the overall assembly (at the
tire), and the wheel itself. Oftentimes, excessive runout can be attributed
to mismount...usually from lack of sufficient lubrication. Also, sometimes
the tire and wheel high spots can be aligned...in effect stacking the two to
one large tolerance. Your better tire dealers may have the equipment/trained
personnel to check this for you.
Be advised if you do have a non-concentric assembly, balancing will only be a
band-aid, if it removes the vibration at all.
Where do you feel the vibration? Steering wheel or seat/floor?
Vibrations that are felt between 50-60 mph, but not above or below are
suspicious though, as that is generally related to axle end runout: hub,
bearings, drum, piloting of wheel to studs, wheel, and tire. Usually the tire
company gets blamed because theirs is the part people see "wobble".
Good luck, and let us know what you find out.
Chris
1967 TR4A
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