Hours at one speed is the hardest test there is
An imbalance produces a vibration at a particular speed. In town a vehicle passes through that speed and leaves it. On a long highway leg it sits in it, continuously, for hours.
That is the worst case for everything the vibration reaches. The tread wears in patches because the same part of the tire is being loaded and unloaded at the same rate for the whole run. The suspension components are being cycled at that frequency without a break. The driver is also absorbing it the entire time, which is the part that does not show up in any maintenance record.
Which means balancing matters more on a corridor vehicle than on a local one, and it matters in a way that is easy to tolerate. A mild vibration is not alarming. It is simply there, for six hours, and it is tiring in a way people attribute to the distance.
Worth reporting even when it is mild
That is the practical point. A driver who mentions a slight shake at highway speed is reporting something worth acting on, and the usual response, that it is only slight, misses what sustained exposure does.
For a fleet, ask specifically rather than waiting. "Does anything vibrate at cruise?" produces answers that "any problems?" does not.
Check the simple things first
In this climate, pressures move around with temperature more than people expect, and a tire well off its specification changes how an assembly behaves.
Set pressures cold against the specification before concluding anything about balance. The national tire and wheel balancing page covers the occasions worth asking for balancing.
When it is not balance
A vibration at every speed, or one with a pull, is alignment or something worn. One that survives a balance is usually the rim, and wheel refurbishing is at this store.
About this store
The Fernley store carries all nine Purcell tire categories and is managed by John Jangula.
See the national tire and wheel balancing page for all 51 locations.