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Discussion Starter #1
will the title say it all i suspect that my vacume brake assist is bad and is the reason my truck has been trying to stall when i use the brakes but i don't know for sure and was wonder if there is a method of testing it before i replace it
 

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Discussion Starter #4
ok so i guess i will by a vacume tester

but how do i know if it assisting me or i not when the truck is off does it make a sound or something ?
 

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Discussion Starter #6
so i ran it then when i stopped it i pumped the brake and it was soft and got firmer the more i times i pushed on it
 

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Pump the brake pedal. You should feel Firm, Firm, Firm, Soft... If not, you may have a vacuum leak in the internal diaphram. Using a vacuum gauge would be best.
??? It's supposed to get harder as you pump it.
 

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??? It's supposed to get harder as you pump it.
You are correct as I misspoke. The point is you should get about three assisted braking pumps until you are out of vacuum and the pedal drops down with no more booster assist. With a hole or tear in the booster diaphram, you will lose vacuum and either hear it or notice your pedal drop.

On my truck, I could not hear a leak but the brakes felt overly mushy with less stopping ability. I replaced the brake booster and, after learning to correctly adjust it, my brakes showed a marked improvement.
 

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Discussion Starter #11
ok thanks for ur help i will replace it soon but i might buy a vacume pump check just because on this truck it would be helpfull to have laying around
 

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cheapest and easiest test is to unplug the vacuum line to the booster (be sure to plug it), start the truck, and hit the brakes. if it doesn't want to die, you know the booster is your issue.
 

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vacuum gauge a waste of money

will the title say it all i suspect that my vacume brake assist is bad and is the reason my truck has been trying to stall when i use the brakes but i don't know for sure and was wonder if there is a method of testing it before i replace it
Apply the brakes and start the engine. If the pedal gets sucked down, it works. If not, it's bad. It's that simple.
 

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Apply the brakes and start the engine. If the pedal gets sucked down, it works. If not, it's bad. It's that simple.
Not always. mine is going but isn't gone. When i start the truck it sucks the pedal down, just not as quickly as it should. I know mine is going since i can hear the vacuum leak inside the truck that varies with pedal position.
 

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You are correct as I misspoke. The point is you should get about three assisted braking pumps until you are out of vacuum and the pedal drops down with no more booster assist. With a hole or tear in the booster diaphram, you will lose vacuum and either hear it or feel more firmness.

On my truck, I could not hear a leak but the brakes felt overly firm with less stopping ability. I replaced the brake booster and, after learning to correctly adjust it, my brakes showed a marked improvement.
so how do you correctly adjust it?
 
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