the idea of ​​an all-terrain vehicle on hydraulic motors

Have an idea to make a mini all-terrain vehicle on the pneumatics 4x4 low pressure drive hydraulic motors, one for each wheel, frame and hydraulic pump in one unit with the engine (for example, from a scooter) and controlled by a control valve.
Is this real?
Can anyone take it?
Pros: frame, constant engine speed, a turn almost in place, a simple layout scheme, it is possible to overcome any water, snow barriers, swamps, etc. It is even possible to think over the installation of the steering wheel.