Ford has ditched plans to use a form of gas-electric hybrid technology to significantly improve the fuel-efficiency of the Explorer, the world’s best-selling SUV. Ford insiders said the decision was made because of a cash shortage and less success than expected with the “integrated starter-generator” technology, which would have saved gas when the vehicle was at a standstill. The technology was integral to the automaker’s plan to boost SUV fuel-efficiency by 25 percent by 2005. A spokesperson said Ford stood by that pledge, and CEO William Clay Ford, Jr., indicated earlier this week that the company was still committed to hybrid versions of the Escape, a smaller SUV.