turbo5.3Z/28

Hey everyone, within the past few months I have noticed that when braking at speeds over 50ish mph that when I go to hit the brake pedal that shortly after the pedal will sink to the floor and there is some loss of braking force. Shortly after the pedal feel is regained and normal braking resumes. I do have a turbo on the car, could this be causing a loss od vacuum to the booster, or could the brake booster itself be going bad?

imma_stocker

iTrader: (19)

Loss of vac and turbo only comes into play when brake boosting.
Booster could be going bad but unlikely depending on age and mileage.

More likely low fluid, worn pads, air in the system, or a leak somewhere downstream.

StealthFormula

iTrader: (35)

If it were me the first thing I would do is completely flush the old brake fluid out and replace with new. Brake fluid with too much water content in it or air can do funny things to the pedal feel and braking force. I prefer to use a Motive power bleeder when I flush/bleed my brakes but that's only one of many different ways to go about it. At the same time I would visually inspect all brake components. Maybe even make sure the caliper slider pins are properly lubed too for good measure. If none of that cures the issue then you can rule those things out and continue to troubleshoot. My next thought would probably be brake booster.

turbo5.3Z/28

The car has 97k on it. Does not get driven as much as it used to. I will give those things a try. could it be due to the age and or milage that the rubber lines could be expanding when the brakes are applied?

Corvett z07

iTrader: (2)

No. The rubber brake lines would have to be very deteriorated and many more miles on them for them to be need replacing if they're causing that bad of pedal feel. 99% sure it's not that, however there's a first for everything...

Spartan7

iTrader: (7)

The vacuum booster does not affect pedal travel, only pedal effort (the force needed by you to apply the brakes). You most likely have air in the system or old brake fluid. Check all your lines and calipers for leaks, and flush with new fluid.

zebrabeefj40

I'll second or third the bet that you need to flush the old brake fluid out and replace with new.


I have also boiled fluid when the pads were thin on my daily driver chitbox but I doubt that is an issue.


Nick

turbo5.3Z/28

OK cool i also failed to mention since i do not drive the care and forgot, it usually happens at higher speeds say 60 mph or higher. don't know if that will change anything