Can anyone help please....
I was just due to pack the Omega ready for out summer holiday, i turned it round ready to load and bang something made a popping noise a bit of graunching from under the bonnet and the steering went so heavy i had to hang from the wheel to move it. So i parked it up and we ended up coming in the wifes car

I would like to hope its a fuse, but im pretty sure its not. I had a quick look under the bonnet and the aux belt is ok ( was replaced not so long ago) and the fluid is high and no leaking anywhere.
The pump has been noisey a bit recently and the steering a little heavy on idle but nothing drastic. I was just going to order a pump online ready to fit on my return but my step dad has just thrown into the equation something about a steering box? could this have failed instead?.
How easy are both of these to change??
Thanks in advance
Matt