Section 187(7) in The M.P. Motor Vehicles Rules, 1994
(7)No tractor shall draw more than three trailers :Provided that no tractor shall draw on a public road-(i)a trailer exceeding five hundred kilograms in weight unladen and fitted with solid steel wheels less than sixty centimetres in diameter;or(ii)a disc harrow without trolley wheel used as trailing implements behind a tractor.
