For maximum power Pontiac recommends premium fuel but says the GT will not be damaged if 87 octane is used. The GT gets an EPA-rated 24 mpg City/32 Highway.
Pontiac did a great job on the feel of the brakes. The pedal was firm but it was easy to slow either a little or a lot. Also, the front of the G5 didn't dip too much under hard braking. That gives it a balanced, secure feel.
The summer performance tires that come on the GT are unsuitable for winter use. They offer so little grip that they are likely to worry even those experienced in winter driving. In packed snow (5F to 20F), we found extremely poor traction even on flat terrain. With little grip, the GT has trouble turning and stopping. The enhanced traction control doesn't solve the problem. Halfway up one hill all it did was to cut the power as it tried to help the wheels regain traction, but the effect was that all the momentum was lost. If you hope to drive the GT in the snow you better budget for four snow tires. Putting snow tires only on the front would help with turning, but with far more slippery tires on the rear wheels the handling could be treacherous. It would be nice if Pontiac would give consumers interested in the GT the choice of the performance tires or regular, all-season radials. Next Page