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Old 08-04-2008, 10:42 AM   #1
phil g
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68 Brake question

I have a 68 with power drum brakes. PO replaced most major brake parts,
master cylinder, booster, drums ,shoes, wheel cylinders. Brakes work but are really touchy. If you are not careful the front brakes lock up. There is very little free play in the brake push rod. I have had a couple of people look at it and say that it looks right. The problem started after the brake system was redone. Any suggestions?
Thanks,
Phil
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Old 08-04-2008, 11:02 AM   #2
stllookn
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Re: 68 Brake question

The power drums on my '68 3/4 t. grab like mad for the first few blocks when I first drive it after about a 1-2 week lay-off. I have never pulled them apart to determine if there is a problem since it goes away once I drive it. I will watch this thread to see if there is fix.
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Old 08-04-2008, 12:19 PM   #3
steelhorse
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Re: 68 Brake question

A lot of times moisture from either rain or high humidity will cause your brakes to "grab" after sitting.Sometime all it takes is overnight,usually hitting the brakes once or twice will clear it up.This even happens on new cars.If your brakes are still grabbing up front you might want to check your adjustment they may be too tight.
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Old 08-04-2008, 02:05 PM   #4
70rs/ss
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Re: 68 Brake question

Man, I tried to post but it didn't go through? Anyways, i'd look at the front shoes being adjusted too close to the drums, since you said it started after new parts.

The other possible cause is that the shoes are two different thicknesses, so maybe the thicker one was put towards the front and is causing it to grab?? The thicker shoe should be towards the rear of the truck (no matter on DS or PS) example, PS the thicker shoe is to your left (facing the drum) and the thinner shoe is to the right or towards the front of the truck. Good luck!!
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Old 08-04-2008, 04:14 PM   #5
LockDoc
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Re: 68 Brake question

..With steelhorse. I think the inside of the drums or the outside of the rotors (depending on what you have) get a little surface rust on them and grab until the surface rust gets worn off. I have the same problem when the humidity is high.

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Last edited by LockDoc; 08-04-2008 at 04:14 PM.
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