rail 14 the cable 95 is passed over a swinging pulley 99 that is suspended from an anchor 100 secured to the sidewall 26 near the front wall 28 of the hopper the cable passing over another swinging pulley 101 that is attached to an anchor 102 located on the side rail 14 the other cable 95 end 98 as shown best in fig2 is connected to a drum 81 a spring 103 is shown connected on one end to rail 14 and on its other end 104 connected to the frame lug 73 for urging the frame 71 to pivot forwardly elevating the wheel 80 out of engagement with tire 21a to drum 81 in operation to pivot the hopper 24 from the tilted dumping position of fig3 raising it to the position of fig1 and 4 the handle 87 is pulled to engage the extension 84 where with continued handle rotation the frame 70 is pivoted clockwise as shown in the figures to place the friction wheel 80 in engagement with the wheel 21a of the trailer fig3 spring 89 is thereby stretched with the undersurface of lug 88 fitted over the bar extension 84 thereby locking the friction wheel against the trailer wheel thereafter movement of the trailer frame 11 forwardly as pulled by a prime mover not shown connected to the tongue 12 turns the trailer wheel 21a counter clockwise as viewed in the figures this in turn rotates the friction wheel 80 that is in engagement with wheel 21a clockwise as viewed in fig3 which then turns the drum 81 in the same direction winding the cable 95 at end 98 onto that drum as the cable 95 winds onto drum 81 cable 95 shortened thereby moving the swinging pulley 99 towards.