I bought a truck and only drove it for 50miles.After that the moter stopped running.Can I get my money back?

Which state? Did you sign a sales contract? Had your mechanic checked it before you bought it?

Private sale? You could ask for your money back but in most states, private sale of cars is considered as-is whether stated or not.

You should have spent $100 and had an independent mechanic go over it before you paid for it, or assumed the risk of this happening. As odinn7 said, private party sales are as-is where-is unless its SPECIFICALLY written they are offering a warranty.

Normally no, I will assume you did not get the vechile checked by a mechanic prior to sale? Private sales are normally "as is" and buyer beware situation.