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Old 06-06-2008, 07:03 AM   #1
jott_06
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brake pedal is to the floor?

I've never had my truck on the road yet but ever since i bought it the brake pedal goes clear to the floor before the brakes grab. What would cause this. We've bled all of the brakes and it hasnt changed anything. The brakes work there just isnt much pedal. By the way it has four wheel drums. Should i just try to adjust them?
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Old 06-06-2008, 07:13 AM   #2
truckdude239
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Re: brake pedal is to the floor?

your drum,s are out of adjustment u need to adjust them till the are just draging when you spin the drum
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Last edited by truckdude239; 06-06-2008 at 07:14 AM.
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Old 06-06-2008, 10:03 AM   #3
68gmsee
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Re: brake pedal is to the floor?

Quote:
Originally Posted by truckdude239 View Post
your drum,s are out of adjustment u need to adjust them till the are just draging when you spin the drum
That's the way I adjudt mine...

You didn't say power or non power brakes but you also need to check to see if the master cylinder is working properly. If it's the original, you may have a defective one and they're fairly cheap.

Some of these are dual stage ones. The first stage may be bad and you then have to depress the pedal further to use the second stage.
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Old 06-06-2008, 11:07 AM   #4
LONGHAIR
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Re: brake pedal is to the floor?

It may be in the drums, but it is also possible that the "freeplay" of the pedal is too loose. With vehicles this old, you never know who has been there before you...or what they have done. If the pedal has to move too far before any fluid is pushed out, adjusting the shoes won't cure the problem.
That is not to say that the shoes dont need some attention, they probably do. But if the master cylinder has been replaced, the pedal push rod may need to be adjusted.
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Old 06-06-2008, 04:33 PM   #5
Longhorn Man
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Re: brake pedal is to the floor?

pump the pedal;
if the pedal rises, hold it firm. 30 - 45 seconds with pressure. Not panic stop pressure, but good preasure.
If the pedal stays up, adjust the shoes.
If the pedal sinks eventually, bleed and retest.
If the pedal does not raise, but remains firm, then check the freeplay on the pedal. best way to do this is by pressing the pedal with your hand. If it feels like you are just pushing against a light spring, your freeplay needs adjusted. You'll want about 1/2 inch if memory serves. Too tight and your brakes will drag as the brake temps rise.
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