This invention provides means, including a platform and means to support same for oscillatory, vibratory motion so that a large size vehicle tire containing dry ballast may be disposed on the platform and thus moved and vibrated whereby an eductor tube connected outwardly to a solids removal pump may have its inner end insertable into the tire to follow the descending level of granular ballast therein to substantially the bottom of the tire, as the platform is supported (a) to move up and down but continuously parallel to the base, (b) or preferably with spring urged, modulatory motion, whereby the upper surface of the ballast is maintained substantially level in descent.