With the Dow closing in on 13,000, some shares are becoming over-priced. Good time to sell? These may not go higher.

ExxonMobil, Inc. (NYSE: XOM) -- The world's largest oil company is up over 20% in the last year. Oil, however, seems to be hanging around $63. Without another jump to $70, the chances that this stock moves up another 10% are probably not good. Not to mention that oil could move down. Remember, the Saudi princes have talked about adding to supply.

Apple, Inc. (NASDAQ: AAPL) -- AAPL shares have run almost 160% over the last two years. They are now caught in a small trading range around $90. Even a tiny bit of bad news about the iPhone could cut the stock price. Assumptions that the iPhone, iPod and Mac are going to do well are probably priced in.

Google, Inc. (NASDAQ: GOOG) -- What a tremendous quarter. It has taken that stock back close to $500. GOOG shares are up 140% in two years. Concerns still linger about cost of servers and all the new employees. Great company. Expensive stock.

AT&T, Inc. (NYSE: T) -- How can a phone company stock be up 70% in two years? Well, as far-fetched as it sounds, AT&T is. But the landline business is being eroded by VoIP. Meanwhile, the cell business in U.S. is starting to get mature as handset penetration rates no longer grow in high double-digits. Competition with Verizon Wireless is likely to keep pricing leverage on cell service low. The company wants to sell Wall Street on fiber-to-the-home technology, getting customers from cable, but that case has yet to be proved.

DaimlerChrysler AG (NYSE: DCX) -- Rumors about Chrysler sales have pushed shares up 30% in two months. But the process of auctioning off the unit is slow and the UAW has said it will try to block a private equity sale. Chrysler still has $15 billion in unfunded pensions and health benefits. No sale of Chrysler, and these shares could go right back to early 2007 levels.

Douglas A. McIntyre is a partner at 24/7 Wall St.