The Clinton administration today will propose regulations that would force big cuts in emissions from new diesel trucks and buses and require that diesel fuel be almost free of sulfur, which can foul up anti-pollution equipment. The EPA estimated that the rules, which would begin going into effect in 2006 and 2007, would cut tailpipe pollution from large trucks and buses by 95 percent. The rules are expected to be made final later this year, though the trucking and petroleum industries are likely to continue fierce lobbying against them. Enviros praised the proposed regulations, noting that large diesel trucks now emit much more soot and smog-causing chemicals than automobiles. Earlier this week, the National Toxicology Program added diesel exhaust particulates to its list of chemicals that are “reasonably anticipated to be a human carcinogen.”