Chevrolet 2010 HHR Owner's Manual page 376

WARNING:
If you use bias-ply tires on the vehicle, the
wheel rim flanges could develop cracks after
many miles of driving. A tire and/or wheel
could fail suddenly, causing a crash. Use
only radial-ply tires with the wheels on the
vehicle.
If you must replace your vehicle's tires with those
that do not have a TPC Spec number, make sure
they are the same size, load range, speed rating,
and construction type (radial and bias belted tires)
as your vehicle's original tires.
Vehicles that have a tire pressure monitoring
system could give an inaccurate low pressure
warning if non TPC Spec rated tires are installed
on your vehicle. Non TPC Spec rated tires may
give a low pressure warning that is higher or lower
than the proper warning level you would get with
TPC Spec rated tires. See Tire Pressure Monitor
System on page 6 64.
Your vehicle's original equipment tires are listed
on the Tire and Loading Information Label. See
Loading the Vehicle on page 5 24, for more
information about the Tire and Loading
Information Label and its location on your vehicle.
6-73