Abstract: A tilt-cab tractor including a chassis, a cab pivotally mounted about an axis near the front of the chassis, a suspension cylinder mounted at each corner of the cab, at least one hydraulic cab tilting cylinder, an accumulator, and a first conduit connecting the accumulator to the suspension cylinders wherein the improvement comprises; a source of pressurized hydraulic fluid for delivering hydraulic fluid to the hydraulic tilting cylinder and the shock absorber suspension cylinders, a second and third hydraulic conduit for delivering hydraulic fluid to the cab tilting cylinder and for delivering hydraulic fluid to the first conduit respectively, a control valve and means for selectively blocking flow of pressurized hydraulic fluid to the accumulator when the tractor brakes are applied.