I know where I can get a deal on a winch but I don't know if it will work on my vehicle. It is a Mile Marker 10,500lb. hydraulic winch. It is from a military Humvee which are 24 volt systems and it uses hydraulic pressure from the power steering system. My questions are 1) Can I convert/reduce the voltage requirement to work on a 12 volt system? 2) Will a non-booster power steering system allow the winch to function properly? Anyone that has any knowledge on this subject please help.

 

This is not specific knowlede of your intention but from life's experiences.
The electric motor won't work very well on 12 volts. It will draw half the current, run half as fast and have half the power.
The hydraulic part could be worked out.
As for the rest, it may be a deal because no one else wants to hassle with it.
By the time your done trying to get a satisfactory setup from cost and wotk standpoint it probably will be worth it to get a new electric wench from one of the known marketers.
I got a 12 volt 5000 lb straight pull light duty for less than $100 and would not even think of trying to rig something up.
The better ones at much more capacity go for upwards of $400+.
I'm not trying to insult you but sometimes even when given something, it's not a deal in the end. Been there before.

 

you will need to change out the swicth relay that the two wires go into on the right side, you can buy it from mile marker for $80, it will work fine with the hudrolic pressure you have you will just have to keep the rpms up and it wont spoole as fast but it will work