Brake failure

Hello, well today I was out driving in the mountains on some Forest Service roads, in my 2004 2wd Ford Ranger, with manual transmission. (And yes, I wish it was 4wd! lol) Anyway, after a mild descent on mildly rocky section, I came across a steep descent with large rocks (ya know ones about the size of my head, lol). Couldn’t back up, tires just spun out. So I had to clear the rocks and proceed onward, at least gravity was working to my advantage. But the pucker factor was high, and in my heightened state I kept the clutch engaged for the aproximately 90 second descent, and was pushing hard on the brakes. Almost immediately I felt the ABS pulsating, and then the pedal went to floor, but luckily regained pressure, and I continued the descent in a safe and uneventful manner. I’m sure if I had released the clutch, that might have helped or I might have just stalled out all toghther.

At any rate, everything seemed fine on the way home, but I’m just curious as why I momentarily lost brake pressure. Thanks to any one who read this whole question!

I think you completely overwhelmed the ABS. It’s definitely possible, the system is supposed to provide a rapidly stuttered braking sequence which you and your foot could not match, but which is limited itself by the laws of physics. The rocks you were driving over probably rolled under your tires, and you didn’t have four wheel drive, so the truck had to rely on the ABS and the front-wheel torque to slow the vehicle. Not good.
When that happened it would feel as if the pressure was lost. In a way it was. If you are going to go four-wheeling, get a four wheeler. With ABS brakes.

thanks kizwiki, figgured somethin’ along those lines happened. Just wasn’t sure if or even if it’s possible to fry/boil/etc. your brake fluid, it’s still full, but I’ll try to remember to open up the reservoir tomorrow and take a sniff, can’t wait! Yep, would like to try to get this truck to ripe old age of 10, but ain’t lookin’ good, lol.

I think you completely overwhelmed the ABS.

I’m curious. This is the first I’ve ever heard of this. Can you explain further what this means and how it can lead to the pedal going to the floor?

I suspicious of the master cylinder, but would be interested to hear more about the ABS.

I am curious about the overwhelmed ABS too, never heard of this. You may have moisture (water) in your brake fluid and could have overheated the brakes causing the water to boil, this would cause the pedal to go to the floor. Once it cooled the water would go from vapor to liquid and your pedal would return to nromal. Suggest you bleed the old fluid out and get some new clean brake fluid in.

alright Steve, thanks, I’ll keep that in mind. Maybe I should also add that at nearly 80,000 miles, I still have all the original front brake hardware. Though the rear shoes got replaced at 35,000 miles and the fluid was done about 2 yrs ago.

Why were your shoes replaced at 35K? If they were just worn out (as opposed to maybe contaminated by fluid or something) and wore out long before the fronts then there is likely some kind of issue with the brakes. Your rear shoes should outlast your front pads by a few brake jobs.

yeah, the mechanic said apparently Ford didn’t adjust them correctly, and had been dragging, and therefore wore prematurely. prolly coulda had 'em fixed under warranty, but good luck with that! yeah everything things been pretty good since then.