I noticed a big puddle of fluid under My truck earlier today, I got down and put My finger to see what it was and its seemed like brake fluid, so I popped the hood and My reservoir was almost empty. I can see fluid all under the reservoir but the lines themselves look fine, I bought some fluid at the store which got Me home but was loosing the brakes as I was stepping on the pedal, got home and reservoir was empty and the brake warning lights are now on. Is it the master cylinder or is it the seals on the reservoir, can I replace the seals on the reservoir or do I replace the the whole unit(master), where's the best place to get these brake parts, thanx in advance to Everyone for Your replies.

 

I suspect the master cyl is source of leak. So you need a reman MC. Not a big deal other than bleeding correctlly. Instructions are generally in package.