In Slaton, FM 400 turns to the north and crosses  US 84 near the southern city limits before entering that city's downtown, where it is concurrent with  Bus. US 84 along 9th Street for .
FM 400 in Slaton turns north and crosses US 84 at the city's southern edge, then enters downtown, where it coincides with Business US 84 on 9th Street for a specified period.