Buick 2011 Regal - Manual (Page 290)

10-54 Vehicle Care
One way to tell when it is time for
new tires is to check the treadwear
indicators, which appear when the
tires have only 1.6 mm (1/16 in) or
less of tread remaining. See Tire
Inspection on page 10‑52 and Tire
Rotation on page 10‑52 for
additional information.
The rubber in tires ages over time.
This is also true for the spare tire,
if the vehicle has one, even if it is
not being used. Multiple conditions
affect how fast this aging takes
place, including temperatures,
loading conditions, and inflation
pressure maintenance. Tires will
typically need to be replaced due to
wear before they may need to be
replaced due to age. Consult the tire
manufacturer for more information
on when tires should be replaced.
Vehicle Storage
Tires age when stored normally
mounted on a parked vehicle. Park
a vehicle that will be stored for at
least a month in a cool, dry, clean
area away from direct sunlight to
slow aging. This area should be free
of grease, gasoline, or other
substances that can deteriorate
rubber.
Parking for an extended period can
cause flat spots on the tires that
may result in vibrations while
driving. When storing a vehicle for
at least a month, remove the tires or
raise the vehicle to reduce the
weight from the tires.
Buying New Tires
GM has developed and matched
specific tires for your vehicle.
The original equipment tires
installed on your vehicle, when
it was new, were designed to
meet General Motors Tire
Performance Criteria
Specification (TPC Spec)
system rating. If you need
replacement tires, GM strongly
recommends that you get tires
with the same TPC Spec rating.
This way, your vehicle will
continue to have tires that are
designed to give the same
performance and vehicle safety,
during normal use, as the
original tires.
GM's exclusive TPC Spec
system considers over a dozen
critical specifications that impact
the overall performance of your
vehicle, including brake system
performance, ride and handling,