Buick RIVIERA 1993 Manual page 252

Wheel Alignment and Tire Balance
w.
The wheels on your vehicle were aligned and balanced
carefully at the factory to give you the longest tire life
and best overall performance.
In most cases, you will not need to have your wheels
aligned again. However, if you notice unusual tire wear
or your vehicle pulling one way or the other, the
alignment may need to be reset. If you notice your
vehicle vibrating when driving on a smooth road, your
wheels may need to be rebalanced.
Wheel Replacement
Replace any wheel that is bent, cracked or badly rusted.
If wheel nuts keep coming loose, the wheel, wheel bolts,
and wheel nuts should be replaced. If the wheel leaks air
out, replace it (except some aluminum wheels, which
can sometimes be repaired). See your Buick dealer if
any of these conditions exist.
Your dealer will know the kind of wheel you need.
Eachnew wheel should have the same load carrying
capacity, diameter, width, offset, and be mounted the
same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts,
or wheel nuts, replace them only with new GM original
equipment parts. This way, you will be sure to have the
right wheel, .wheel bolts, and wheel nuts for your Buick
model.
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