DETROIT -- Today's early holiday close of the stock market brought an end to one of the most tumultuous weeks for the auto industry in recent memory, as the price of oil rose and the value of auto stocks fell.

Gasoline and oil closed at record highs. The price of self-serve regular unleaded gasoline is at a national average of just under $4.10 a gallon, according to AAA, of Heathrow, Fla. That's up $1.15 from one year ago. The price of oil reached as high as $145.85 today -- a record -- before closing at $145.29

For the third straight week, the average price of diesel fuel was $4.76. While diesel's price has stabilized in recent weeks, it costs $1.86 more than it did a year ago, according to AAA.
General Motors and other auto stocks skidded in the opposite direction. GM shares were down about 12 percent for the week, closing at $10.17 per share. But that was up slightly from the 54-year low of $9.98 at the market's close Wednesday, July 2.

GM's market capitalization, or the total value of outstanding shares, finished at $5.76 billion, down $780 million for the week

Since Feb. 1 -- when GM was trading for $28.98 -- shares have lost nearly two-thirds of their value, and analysts are speculating about the company's liquidity.

Ford Motor Co.'s stock finished down 11 percent for the week, closing at $4.42 per share. Ford's market capitalization ended the week at $9.91 billion, down $1.2 billion.
Also dropping were the stocks of dealership groups. Since their market close on Friday, June 27, shares of the following dealership groups have dropped by double-digit percentages:
• AutoNation Inc.: down 13.9 percent
• Sonic Automotive Inc.: down 12.58 percent
• Group 1 Automotive Inc.: down 12.3 percent
• Asbury Automotive Group: down 17.1 percent
• Lithia Motors Inc.: down 12.6 percent