Unstopable Brake Fluid Spillage!

[BowtieBlazer]

I can't keep from loosing brake fluid! I have changed the cap because it always seemed to spill past the cap. Next I changed the rubber insert...still no luck...First time it spilt I expected it because I was jumping dunes. Now its aggrivating it spills during everyday driving...Probably shifting like I am jumping dunes but still! Someone has to know how to keep the fluid in the resevoir and off the firewall and inner fenders. (If you don't know brake fluid is highly corrosive!)

 

[YtseJam]

If it is coming out of the master cylinder reservoir, I'd suggest replacing it.

 

[BowtieBlazer]

Yeah its coming out the master cylinder resevoir. Like I said in the previous post i've replaced about everything but the actual resevoir. Its leaking from the cap not the base.

 

[Blazinaire]

Does your truck have the plastic cap and reservoir? Mine did that a couple times and I noticed that the cap wasn't snapping on correctly. If the seal is good and the cap is too, then you kinda have to eliminate those as possibilities and that would leave the reservoir itself. Hell, they aren't all that expensive to replace anyway and if that is the only thing that you haven't replaced you might as well.

 

[Grim-Reaper]

You do realize there is a weep hole in the base of the master where it meets the booster. If the seals leak in the master then the fluid will leak into the front of the booster then back out that weep hole. If it's wet down the front of the booster it may well be the master is shot.

 

[rampage]

I've been told that the way to check for a bad master cylinder is to clamp off the rubber hoses that go to the front discs and the brake hose in the rear with 'brake clamps'. Then apply the pedal to check for pressure. If no pressure then the master is bad (this assumes that there aren't any other leaks of course). Can any one verify this?