Parked truck the other day. ambient temp approx 115, coolant temp on gauge approx 225. returned to find extreme brake fade, pedal almost to floor on initial application. I have flushed brake fluid even though truck is only 1 yr old with 3000 miles. Installed castrol lma dot3-4, no help. Incident has occurred several times under similar conditions and is repeatable. My conclusion is that even though coolant temps are not "over the limit" excessive, it is obvious that underhood temps are borderline and that addressing that issue will probably be beneficial all around.
Extreme underhood temps also affecting brakes
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If dealer can't find it
go to DOT 5 which is silicone and is very high heat resistant. Nice thing on the side is silicone will not attack any parts of your brake system. I have used it for past 17 years in my plane. :cool
go to DOT 5 which is silicone and is very high heat resistant. Nice thing on the side is silicone will not attack any parts of your brake system. I have used it for past 17 years in my plane. :cool
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I hope your not the pilot for Air France LOLYaller Dog said:
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Had the same issue as well. My expectation is that it is associated with the setting and release of the parking brake as the condition only occurs on the first stop after release and not every time. Still pondering the reasons why though.
Brake fluid - Dot 3 and 4 fluids do not attack components in the braking system either. They are, by design, hygroscopic so they will absorb any water that gets into the system.
Dot 5 is not and water will pool with the potential to boil when hot thereby creating a bubble in the system and making that portion of the system nearly inoperative. Also Dot 5 is more compressible than Dot 3 & 4 so you will get a slightly softer pedal.
Bottom line is Dot 5 is fine for show or rarely driven cars.
Dot 3 & 4 are better for daily drivers - just be sure to change the fluid every few years.
Brake fluid - Dot 3 and 4 fluids do not attack components in the braking system either. They are, by design, hygroscopic so they will absorb any water that gets into the system.
Dot 5 is not and water will pool with the potential to boil when hot thereby creating a bubble in the system and making that portion of the system nearly inoperative. Also Dot 5 is more compressible than Dot 3 & 4 so you will get a slightly softer pedal.
Bottom line is Dot 5 is fine for show or rarely driven cars.
Dot 3 & 4 are better for daily drivers - just be sure to change the fluid every few years.
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