Gas above $4 a gallon changes the ownership math for some vehicles much faster than it changes the sticker price. A large SUV or performance pickup can still make perfect sense for someone who tows, hauls, or needs its capabilities, but casual driving becomes harder to justify when fuel consumption stays high.
AAA put the national average for regular gasoline at $4.43 on September 17, and the daily national average reached about $4.47 by September 20. California and several other states were already well above that level.