A few weeks ago I took my 4mula on a trip from Florida to NY. The trip was a blast as I was free of my wife and kids. Just me on th open road. But along the way, I noticed that my braking ability went south over a long period of driving. The brake light would come on when I applied the brakes. This happened even going thru Washington DC. When I stopped for fuel and a ****, the brakes would come back. I am thinking that maybe my headers are just a little too close to the prop valve and may have caused the fluid to boil. What does the board think? I haven't driven it since I got back because I am too lazy to even wash it right now.

 

the pads might be rubbing too hard against the rotor causing them to overheat -that would cause fade with distance -it might also cause serious damage such as cracks -but I can't think of anything else right now... sorry

 

My headers, along w/ many other peoples headers run pretty close to the brake lines and nobody has had this problem before (not that it can't happen, just seems unlikely.

I thinking more on the lines of a brake dragging. Maybe like a bad rubber line holding pressure on a certain wheel. The longer you drive, the hotter it will get and eventually boil.

Just some thoughts. If you are concerned about the heat of the headers, put some heat shielding around the lines and prop valve.

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'97 Bonneville SSE

 

hey,

this may not be the case, but I had this happen on the racecar before (TransAm Series camaros and mustangs). If your rotors are warped you'll get pad knockback. This pushes all pistons back into the calipers. The first time you push the pedal, all the travel is used to push the pads back up to the rotor. then the brakes are fine...until the end of the next straight.
Probably not your problem buy who knows, it could be a contributing factor (do our calipers have anti-knockback stprings...anyone?)

Clem

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Clem
SCCA TransAm Series Race Mechanic/CrewChief
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1983 Z28 with LG4, 5 speed, and (unfortunately) T-tops
1983 Z28, NO T-tops, (unfortunately) Auto Transmission (hopefully not for long)

 

I have had the brake fluid boil from excessive use in hilly country with much the same symptoms as you are describing. I would replace the fluid first. It doesn't take too much water or other contamination in brake fluid to drastically lower it's boiling point.