Removes cap on number of vehicles that may participate in program. Increases from 17 to 20 miles per gallon minimum rating required for program. Exempts vehicles with rating of 40 miles per gallon or more from additional registration fees. Requires payment of additional registration fees for exempt vehicle if owner ends voluntary participation in program. Changes per-mile road usage charge to five percent of rate of per-gallon gasoline license tax. Provides for reconciliation when amount of fuel taxes paid by person with respect to subject vehicle for reporting period is less than or exceeds per-mile road usage charge owing for such reporting period. Requires Department of Transportation to consult with vehicle dealers to determine how to encourage at point of sale participation in per-mile road usage charge program. Grants department general rulemaking authority for per-mile road usage charge program. Takes effect on 91st day following adjournment sine die.